Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2019	Nov. 01, 2019
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q3
Trading Symbol	NL
Title of 12(b) Security	Common stock
Security Exchange Name	NYSE
Entity Registrant Name	NL INDUSTRIES INC
Entity Central Index Key	0000072162
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		48,755,734
Entity File Number	1-640
Entity Incorporation, State or Country Code	NJ
Entity Tax Identification Number	13-5267260
Entity Address, Address Line One	5430 LBJ Freeway, Suite 1700
Entity Address, City or Town	Dallas
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75240-2620
City Area Code	(972)
Local Phone Number	233-1700
Document Quarterly Report	true
Document Transition Report	false

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 109,419	$ 116,259
Restricted cash and cash equivalents	2,913	3,727
Accrued insurance recovery related to litigation settlement		15,000
Accounts and other receivables, net	13,797	12,440
Inventories, net	18,826	17,102
Receivable from affiliates	648	792
Prepaid expenses and other	1,149	1,324
Total current assets	146,752	166,644
Other assets:
Restricted cash and cash equivalents	25,310	1,003
Notes receivable from affiliate	36,700	34,000
Marketable securities	27,309	27,740
Investment in Kronos Worldwide, Inc.	257,717	255,565
Goodwill	27,156	27,156
Other assets, net	3,187	3,108
Total other assets	377,379	348,572
Property and equipment:
Land	4,940	5,151
Buildings	22,856	22,842
Equipment	67,595	67,446
Construction in progress	963	603
Property and equipment, gross	96,354	96,042
Less accumulated depreciation	65,137	64,016
Net property and equipment	31,217	32,026
Total assets	555,348	547,242
Current liabilities:
Accounts payable	4,987	4,831
Accrued litigation settlement	11,774	60,000
Accrued and other current liabilities	9,797	10,854
Accrued environmental remediation and related costs	3,168	5,027
Payable to affiliates	567	567
Income taxes	64	44
Total current liabilities	30,357	81,323
Noncurrent liabilities:
Long-term debt from affiliate	500	500
Accrued pension costs	7,689	10,389
Accrued environmental remediation and related costs	91,808	93,184
Long-term litigation settlement	59,797	17,000
Deferred income taxes	31,956	31,373
Other	9,780	9,915
Total noncurrent liabilities	201,530	162,361
NL stockholders' equity:
Common stock	6,094	6,090
Additional paid-in capital	299,102	301,139
Retained earnings	244,700	225,156
Accumulated other comprehensive loss	(248,812)	(248,270)
Total NL stockholders' equity	301,084	284,115
Noncontrolling interest in subsidiary	22,377	19,443
Total equity	323,461	303,558
Total liabilities and equity	555,348	547,242
Commitments and contingencies (Note 14)

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Statement [Abstract]
Net sales	$ 29,703	$ 30,029	$ 94,610	$ 90,827
Cost of sales	20,227	20,433	64,571	60,494
Gross margin	9,476	9,596	30,039	30,333
Selling, general and administrative expense	5,210	5,075	15,860	15,455
Other operating income (expense):
Insurance recoveries	243	526	5,240	889
Other income, net	4,424	18	4,433	645
Litigation settlement expense, net	305		(19,266)	(62,000)
Corporate expense	(3,429)	(1,583)	(9,148)	(14,352)
Income (loss) from operations	5,809	3,482	(4,562)	(59,940)
Equity in earnings of Kronos Worldwide, Inc.	5,463	9,905	23,632	55,029
Other income (expense):
Marketable equity securities	(15,379)	(35,645)	(431)	(55,911)
Other components of net periodic pension and OPEB cost	(434)	(99)	(1,290)	(297)
Interest and dividend income	1,571	1,336	5,213	3,630
Interest expense	(314)	(9)	(332)	(25)
Income (loss) before income taxes	(3,284)	(21,030)	22,230	(57,514)
Income tax expense (benefit)	(2,286)	(6,158)	942	(15,416)
Net income (loss)	(998)	(14,872)	21,288	(42,098)
Noncontrolling interest in net income of subsidiary	540	514	1,744	1,654
Net income (loss) attributable to NL stockholders	$ (1,538)	$ (15,386)	$ 19,544	$ (43,752)
Amounts attributable to NL stockholders:
Basic and diluted net income (loss) per share	$ (0.03)	$ (0.32)	$ 0.40	$ (0.90)
Weighted average shares used in the calculation of net income (loss) per share	48,756	48,727	48,741	48,721

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Net income (loss)	$ (998)	$ (14,872)	$ 21,288	$ (42,098)
Other comprehensive income (loss), net of tax:
Currency translation	(4,500)	1,103	(2,805)	(2,414)
Total other comprehensive income (loss), net	(3,747)	1,997	(542)	299
Comprehensive income (loss)	(4,745)	(12,875)	20,746	(41,799)
Comprehensive income attributable to noncontrolling interest	540	514	1,744	1,654
Comprehensive income (loss) attributable to NL stockholders	(5,285)	(13,389)	19,002	(43,453)
Defined Benefit Pension Plans
Other comprehensive income (loss), net of tax:
Defined benefit plans	818	959	2,463	2,916
Other Postretirement Benefit Plans
Other comprehensive income (loss), net of tax:
Defined benefit plans	$ (65)	$ (65)	$ (200)	$ (203)

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY - USD ($) $ in Thousands	Total	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive income (loss)	Noncontrolling interest in subsidiary
Beginning Balance at Dec. 31, 2017	$ 353,078	$ 6,089	$ 300,866	$ 220,104	$ (191,737)	$ 17,756
Change in accounting principle - ASU 2016-01 at Dec. 31, 2017				46,069	(46,069)
Balance at January 1, 2018, as adjusted at Dec. 31, 2017	353,078	6,089	300,866	266,173	(237,806)	17,756
Net income (loss)	14,736			14,249		487
Other comprehensive income (loss), net of tax	3,501				3,501
Dividends paid to noncontrolling interest	(83)					(83)
Ending Balance at Mar. 31, 2018	371,232	6,089	300,866	280,422	(234,305)	18,160
Beginning Balance at Dec. 31, 2017	353,078	6,089	300,866	220,104	(191,737)	17,756
Change in accounting principle - ASU 2016-01 at Dec. 31, 2017				46,069	(46,069)
Balance at January 1, 2018, as adjusted at Dec. 31, 2017	353,078	6,089	300,866	266,173	(237,806)	17,756
Net income (loss)	(42,098)
Other comprehensive income (loss), net of tax	299
Ending Balance at Sep. 30, 2018	311,320	6,090	301,139	222,421	(237,507)	19,177
Beginning Balance at Mar. 31, 2018	371,232	6,089	300,866	280,422	(234,305)	18,160
Net income (loss)	(41,962)			(42,615)		653
Other comprehensive income (loss), net of tax	(5,199)				(5,199)
Issuance of NL common stock	120	1	119
Dividends paid to noncontrolling interest	(84)					(84)
Other, net	172		154			18
Ending Balance at Jun. 30, 2018	324,279	6,090	301,139	237,807	(239,504)	18,747
Net income (loss)	(14,872)			(15,386)		514
Other comprehensive income (loss), net of tax	1,997				1,997
Dividends paid to noncontrolling interest	(84)					(84)
Ending Balance at Sep. 30, 2018	311,320	6,090	301,139	222,421	(237,507)	19,177
Beginning Balance at Dec. 31, 2018	303,558	6,090	301,139	225,156	(248,270)	19,443
Net income (loss)	15,726			15,204		522
Other comprehensive income (loss), net of tax	733				733
Dividends paid to noncontrolling interest	(117)					(117)
Ending Balance at Mar. 31, 2019	319,900	6,090	301,139	240,360	(247,537)	19,848
Beginning Balance at Dec. 31, 2018	303,558	6,090	301,139	225,156	(248,270)	19,443
Net income (loss)	21,288
Other comprehensive income (loss), net of tax	(542)
Ending Balance at Sep. 30, 2019	323,461	6,094	299,102	244,700	(248,812)	22,377
Beginning Balance at Mar. 31, 2019	319,900	6,090	301,139	240,360	(247,537)	19,848
Net income (loss)	6,560			5,878		682
Other comprehensive income (loss), net of tax	2,472				2,472
Issuance of NL common stock	100	4	96
Dividends paid to noncontrolling interest	(118)					(118)
Equity transactions with noncontrollinginterest, net and other	(288)		(1,831)			1,543
Ending Balance at Jun. 30, 2019	328,626	6,094	299,404	246,238	(245,065)	21,955
Net income (loss)	(998)			(1,538)		540
Other comprehensive income (loss), net of tax	(3,747)				(3,747)
Dividends paid to noncontrolling interest	(118)					(118)
Other, net	(302)		(302)
Ending Balance at Sep. 30, 2019	$ 323,461	$ 6,094	$ 299,102	$ 244,700	$ (248,812)	$ 22,377

- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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+ Details

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Cash flows from operating activities:
Net income (loss)	$ 21,288	$ (42,098)
Depreciation and amortization	2,739	2,609
Deferred income taxes	913	(16,624)
Equity in earnings of Kronos Worldwide, Inc.	(23,632)	(55,029)
Dividends received from Kronos Worldwide, Inc.	19,017	17,961
Marketable equity securities	431	55,911
Cash funding of benefit plans in excess of net benefit plan expense	(1,658)	(2,074)
Net gain from sale of excess property	(4,424)
Other, net	211	426
Change in assets and liabilities:
Accounts and other receivables, net	13,627	(18,203)
Inventories, net	(1,888)	(1,935)
Prepaid expenses and other	175	110
Accounts payable and accrued liabilities	(25,842)	62,025
Income taxes	20	11
Accounts with affiliates	144	2,939
Accrued environmental remediation and related costs	(3,235)	(428)
Other noncurrent assets and liabilities, net	19,516	16,698
Net cash provided by operating activities	17,402	22,299
Cash flows from investing activities:
Capital expenditures	(2,453)	(2,043)
Promissory notes receivable from affiliate:
Loans	(28,100)	(39,000)
Collections	25,400	44,200
Proceeds from sale of excess property	4,636
Other, net	121	225
Net cash provided by (used in) investing activities	(396)	3,382
Cash flows from financing activities -
Distributions to noncontrolling interests in subsidiary	(353)	(251)
Cash and cash equivalents and restricted cash and cash equivalents - net change from:
Operating, investing and financing activities	16,653	25,430
Balance at beginning of period	120,989	102,941
Balance at end of period	137,642	128,371
Supplemental disclosures - cash paid (received) for:
Interest	27	25
Income taxes, net	$ (227)	$ (1,740)

Organization and Basis of Presentation

9 Months Ended

Sep. 30, 2019

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Organization and basis of presentation

Note 1 – Organization and basis of presentation:

Organization – At September 30, 2019, Valhi, Inc. (NYSE: VHI) held approximately 83% of our outstanding common stock and a wholly-owned subsidiary of Contran Corporation (“Contran”) held approximately 92% of Valhi’s outstanding common stock. At September 30, 2019, a majority of Contran’s outstanding voting stock is held directly by Lisa K. Simmons and Serena Simmons Connelly and various family trusts established for the benefit of Ms. Simmons and Ms. Connelly and their children and for which Ms. Simmons or Ms. Connelly, as applicable, serves as trustee. In addition, each of Ms. Simmons and Ms. Connelly serves as co-chair of the Contran board of directors. The remainder of Contran’s outstanding voting stock is held by another trust (the “Family Trust”), which was established for the benefit of Ms. Simmons and Ms. Connelly and their children and for which a third-party financial institution serves as trustee. Consequently, at September 30, 2019, Ms. Simmons, Ms. Connelly and the Family Trust may be deemed to control Contran, and therefore may be deemed to indirectly control the wholly-owned subsidiary of Contran, Valhi and us.

Basis of presentation – Consolidated in this Quarterly Report are the results of our majority-owned subsidiary, CompX International Inc. We also own 30% of Kronos Worldwide, Inc. (Kronos). CompX (NYSE American: CIX) and Kronos (NYSE: KRO) each file periodic reports with the Securities and Exchange Commission (SEC).

The unaudited Condensed Consolidated Financial Statements contained in this Quarterly Report have been prepared on the same basis as the audited Consolidated Financial Statements in our Annual Report on Form 10-K for the year ended December 31, 2018 that we filed with the SEC on March 11, 2019 (the 2018 Annual Report). In our opinion, we have made all necessary adjustments (which include only normal recurring adjustments) in order to state fairly, in all material respects, our consolidated financial position, results of operations and cash flows as of the dates and for the periods presented. We have condensed the Consolidated Balance Sheet at December 31, 2018 contained in this Quarterly Report as compared to our audited Consolidated Financial Statements at that date, and we have omitted certain information and footnote disclosures (including those related to the Consolidated Balance Sheet at December 31, 2018) normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (GAAP). Our results of operations for the interim periods ended September 30, 2019 may not be indicative of our operating results for the full year. The Condensed Consolidated Financial Statements contained in this Quarterly Report should be read in conjunction with our 2018 Consolidated Financial Statements contained in our 2018 Annual Report.

Unless otherwise indicated, references in this report to “NL,” “we,” “us” or “our” refer to NL Industries, Inc. and its subsidiaries and affiliate, Kronos, taken as a whole.

Accounts and Other Receivables, Net

9 Months Ended

Sep. 30, 2019

Receivables [Abstract]

Accounts and other receivables, net

Note 2 – Accounts and other receivables, net:

	December 31,			September 30,
	2018			2019
	(In thousands)
Trade receivables - CompX	$	12,210		$	13,503
Accrued insurance recoveries		266			289
Other receivables		34			75
Allowance for doubtful accounts		(70	)		(70	)

Total	$	12,440		$	13,797

Accrued insurance recoveries are discussed in Note 14.

Inventories, Net

9 Months Ended

Sep. 30, 2019

Inventory Disclosure [Abstract]

Inventories, net

Note 3 – Inventories, net:

	December 31,		September 30,
	2018		2019
	(In thousands)
Raw materials	$	2,661	$	3,313
Work in process		11,130		11,952
Finished products		3,311		3,561

Total	$	17,102	$	18,826

Marketable Securities

9 Months Ended

Sep. 30, 2019

Investments Debt And Equity Securities [Abstract]

Marketable securities

Note 4 – Marketable securities:

Our marketable securities consist of investments in the publicly-traded shares of our immediate parent company Valhi, Inc. All of our marketable securities are accounted for as available-for-sale securities, which are carried at fair value using quoted market prices in active markets representing a Level 1 input within the fair value hierarchy. Any unrealized gains or losses on the securities are recognized in Marketable equity securities on our Condensed Consolidated Statements of Operations.

	Fair value measurement level	Market value		Cost basis		Unrealized gain
		(In thousands)
December 31, 2018
Valhi common stock	1	$	27,740	$	24,347	$	3,393

September 30, 2019
Valhi common stock	1	$	27,309	$	24,347	$	2,962

At December 31, 2018 and September 30, 2019, we held approximately 14.4 million shares of common stock of Valhi. See Note 1. At December 31, 2018 and September 30, 2019, the quoted per share market price of Valhi common stock was $1.93 and $1.90, respectively.

The Valhi common stock we own is subject to the restrictions on resale pursuant to certain provisions of the SEC Rule 144. In addition, as a majority-owned subsidiary of Valhi, we cannot vote our shares of Valhi common stock under Delaware General Corporation Law, but we do receive dividends from Valhi on these shares, when declared and paid.

In March 2019, Valhi filed a Form S-3 registration statement with the SEC, registering our shares of Valhi common stock for resale. The registration statement has been declared effective by the SEC. We may sell all or a portion of such shares from time to time directly or through one or more underwriters, broker-dealers or agents. If the shares are sold through underwriters or broker-dealers, we would be responsible for underwriting discounts or commissions or agents’ commissions. The shares may be sold in one or more transactions at fixed prices, prevailing market prices determined at the time of the sale, varying prices determined at the time of sale or negotiated prices (in each case we may determine). We agreed to reimburse Valhi for its expenses incurred in connection with such registration statement (which expenses were not material). We have not sold any of our shares of Valhi common stock under the registration statement.

Investment in Kronos Worldwide, Inc.

9 Months Ended

Sep. 30, 2019

Equity Method Investments And Joint Ventures [Abstract]

Investment in Kronos Worldwide, Inc.

Note 5 – Investment in Kronos Worldwide, Inc.:

At December 31, 2018 and September 30, 2019, we owned approximately 35.2 million shares of Kronos common stock. At September 30, 2019, the quoted market price of Kronos’ common stock was $12.37 per share, or an aggregate market value of $435.7 million. At December 31, 2018, the quoted market price was $11.52 per share, or an aggregate market value of $405.7 million.

The change in the carrying value of our investment in Kronos during the first nine months of 2019 is summarized below.

	Amount
	(In millions)
Balance at the beginning of the period	$	255.5
Equity in earnings of Kronos		23.6
Dividends received from Kronos		(19.0	)
Equity in Kronos' other comprehensive income:
Currency translation		(3.5	)
Defined benefit pension plans		2.0
Equity in Kronos' treasury stock acquired		(.9	)

Balance at the end of the period	$	257.7

Selected financial information of Kronos is summarized below:

	December 31,		September 30,
	2018		2019
	(In millions)
Current assets	$	1,201.4	$	1,186.9
Property and equipment, net		486.4		465.5
Investment in TiO₂ joint venture		81.3		83.1
Other noncurrent assets		129.0		149.4

Total assets	$	1,898.1	$	1,884.9

Current liabilities	$	233.4	$	227.5
Long-term debt		455.1		434.6
Accrued pension costs		262.9		249.3
Other noncurrent liabilities		106.9		126.6
Stockholders' equity		839.8		846.9

Total liabilities and stockholders' equity	$	1,898.1	$	1,884.9

	Three months ended				Nine months ended
	September 30,				September 30,
	2018		2019		2018		2019
	(In millions)
Net sales	$	410.3	$	437.4	$	1,312.5	$	1,358.4
Cost of sales		291.2		349.7		846.8		1,051.9
Income from operations		58.1		33.1		285.5		128.6
Income tax expense		14.1		6.3		75.5		30.5
Net income		32.6		17.9		181.0		77.7

Other Noncurrent Assets, Net

9 Months Ended

Sep. 30, 2019

Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]

Other noncurrent assets, net

Note 6 – Other noncurrent assets, net:

	December 31,		September 30,
	2018		2019
	(In thousands)
Pension asset	$	1,898	$	1,948
Other		1,210		1,239

Total	$	3,108	$	3,187

Accrued and Other Current Liabilities

9 Months Ended

Sep. 30, 2019

Payables And Accruals [Abstract]

Accrued and other current liabilities

Note 7 – Accrued and other current liabilities:

	December 31,		September 30,
	2018		2019
	(In thousands)
Employee benefits	$	9,001	$	7,742
Other		1,853		2,055

Total	$	10,854	$	9,797

Other Noncurrent Liabilities

9 Months Ended

Sep. 30, 2019

Other Liabilities Disclosure [Abstract]

Other noncurrent liabilities

Note 9 – Other noncurrent liabilities:

	December 31,		September 30,
	2018		2019
	(In thousands)
Reserve for uncertain tax positions	$	7,312	$	7,312
OPEB		1,519		1,409
Insurance claims and expenses		621		621
Other		463		438

Total	$	9,915	$	9,780

Revenue Recognition

9 Months Ended

Sep. 30, 2019

Revenue From Contract With Customer [Abstract]

Revenue Recognition

Note 10 – Revenue recognition:

The following table disaggregates our net sales by reporting unit, which are the categories that depict how the nature, amount, timing and uncertainty of revenue and cash flows are affected by economic factors.

	Three months ended				Nine months ended
	September 30,				September 30,
	2018		2019		2018		2019
	(In thousands)
Net sales:
Security Products	$	24,541	$	23,405	$	75,845	$	75,036
Marine Components		5,488		6,298		14,982		19,574
Total	$	30,029	$	29,703	$	90,827	$	94,610

Employee Benefit Plans

9 Months Ended

Sep. 30, 2019

Compensation And Retirement Disclosure [Abstract]

Employee benefit plans

Note 11 – Employee benefit plans:

The components of net periodic defined benefit pension cost are presented in the table below.

	Three months ended						Nine months ended
	September 30,						September 30,
	2018			2019			2018			2019
	(In thousands)
Interest cost	$	372		$	474		$	1,116		$	1,422
Expected return on plan assets		(590	)		(477	)		(1,770	)		(1,431	)
Recognized actuarial losses		365			406			1,095			1,218

Total	$	147		$	403		$	441		$	1,209

We currently expect our 2019 contributions to our defined benefit pension plans to be approximately $3.3 million.

Income Taxes

9 Months Ended

Sep. 30, 2019

Income Tax Disclosure [Abstract]

Income taxes

Note 12 – Income taxes:

	Three months ended						Nine months ended
	September 30,						September 30,
	2018			2019			2018			2019
	(In millions)
Expected tax expense (benefit), at U.S. federal statutory income tax rate of 21%	$	(4.4	)	$	(.7	)	$	(12.1	)	$	4.7
Rate differences on equity in earnings of Kronos		(1.9	)		(1.5	)		(4.3	)		(4.0	)
U.S. state income taxes and other, net		.2			(.1	)		1.0			.2

Income tax expense (benefit)	$	(6.1	)	$	(2.3	)	$	(15.4	)	$	.9

Comprehensive provision for income taxes (benefit) allocable to:
Net income (loss)	$	(6.1	)	$	(2.3	)	$	(15.4	)	$	.9
Additional paid-in capital		-			(.2	)		-			(.2	)
Other comprehensive income (loss):
Currency translation		.3			(1.2	)		(.6	)		(.7	)
Pension plans		.3			.3			.8			.7
OPEB plans		(.1	)		(.1	)		(.1	)		(.1	)

Total	$	(5.6	)	$	(3.5	)	$	(15.3	)	$	.6

In accordance with GAAP, we recognize deferred income taxes on our undistributed equity in earnings (losses) of Kronos. Because we and Kronos are part of the same U.S. federal income tax group, any dividends we receive from Kronos are nontaxable to us. Accordingly, we do not recognize and we are not required to pay income taxes on dividends from Kronos. We received aggregate dividends from Kronos of $18.0 million in the first nine months of 2018 and $19.0 million in the first nine months of 2019. The amounts shown in the above table of our income tax rate reconciliation for rate differences on equity in earnings of Kronos primarily represents the income tax benefit associated with such non-taxability of the dividends we receive from Kronos, as it relates to the amount of deferred income taxes we recognize on our undistributed equity in earnings (losses) of Kronos.

Income tax matters related to Kronos

Kronos records global intangible low-tax income (GILTI) tax as a current-period expense when incurred under the period cost method. Kronos has evaluated the tax impact of GILTI and base erosion anti abuse tax (BEAT) provisions and related U.S. tax credit provisions applicable to tax years beginning in 2018 based on the relevant statutes, including final GILTI and foreign tax credit regulations issued by the IRS in June 2019 which did not materially impact its determinations with respect to such items.

None of Kronos’ U.S. and non-U.S. tax returns are currently under examination. As a result of prior audits in certain jurisdictions, which are now settled, in 2008 Kronos filed Advance Pricing Agreement Requests with the tax authorities in the U.S., Canada and Germany. During the first quarter of 2018, Kronos’ German subsidiary executed and finalized the related Advance Pricing Agreement with the Competent Authority for Germany (the “Canada-Germany APA”) effective for tax years 2005 - 2017. In the first quarter of 2018, Kronos recognized a net $1.4 million non-cash income tax benefit related to an APA tax settlement payment between its German and Canadian subsidiaries.

Accumulated Other Comprehensive Loss

9 Months Ended

Sep. 30, 2019

Stockholders Equity Note [Abstract]

Accumulated other comprehensive loss

Note 13 – Accumulated other comprehensive loss:

Changes in accumulated other comprehensive loss attributable to NL stockholders, including amounts resulting from our investment in Kronos Worldwide (see Note 5), are presented in the table below.

	Three months ended						Nine months ended
	September 30,						September 30,
	2018			2019			2018			2019
	(In thousands)

Accumulated other comprehensive loss, net of tax:
Currency translation:
Balance at beginning of period	$	(167,984	)	$	(170,739	)	$	(164,467	)	$	(172,434	)
Other comprehensive income (loss)		1,103			(4,500	)		(2,414	)		(2,805	)

Balance at end of period	$	(166,881	)	$	(175,239	)	$	(166,881	)	$	(175,239	)

Defined benefit pension plans:
Balance at beginning of period	$	(70,994	)	$	(73,641	)	$	(72,951	)	$	(75,286	)
Other comprehensive income - amortization of net losses included in net periodic pension cost		959			818			2,916			2,463

Balance at end of period	$	(70,035	)	$	(72,823	)	$	(70,035	)	$	(72,823	)

OPEB plans:
Balance at beginning of period	$	(526	)	$	(685	)	$	(388	)	$	(550	)
Other comprehensive loss - amortization of net gains included in net periodic OPEB cost		(65	)		(65	)		(203	)		(200	)

Balance at end of period	$	(591	)	$	(750	)	$	(591	)	$	(750	)

Marketable securities:
Balance at beginning of period	$	-		$	-		$	46,069		$	-
Change in accounting principle		-			-			(46,069	)		-

Balance at end of period	$	-		$	-		$	-		$	-

Total accumulated other comprehensive loss:
Balance at beginning of period	$	(239,504	)	$	(245,065	)	$	(191,737	)	$	(248,270	)
Change in accounting principle		-			-			(46,069	)		-
Balance at beginning of period, as adjusted		(239,504	)		(245,065	)		(237,806	)		(248,270	)
Other comprehensive income (loss)		1,997			(3,747	)		299			(542	)

Balance at end of period	$	(237,507	)	$	(248,812	)	$	(237,507	)	$	(248,812	)

See Note 11 for amounts related to our defined benefit pension plans.

Commitments and Contingencies

9 Months Ended

Sep. 30, 2019

Commitments And Contingencies Disclosure [Abstract]

Commitments and contingencies

Note 14 – Commitments and contingencies:

General

We are involved in various environmental, contractual, product liability, patent (or intellectual property), employment and other claims and disputes incidental to our current and former businesses. At least quarterly our management discusses and evaluates the status of any pending litigation or claim to which we are a party or which has been asserted against us. The factors considered in such evaluation include, among other things, the nature of such pending cases and claims, the status of such pending cases and claims, the advice of legal counsel and our experience in similar cases and claims (if any). Based on such evaluation, we make a determination as to whether we believe (i) it is probable a loss has been incurred, and if so if the amount of such loss (or a range of loss) is reasonably estimable, or (ii) it is reasonably possible but not probable a loss has been incurred, and if so if the amount of such loss (or a range of loss) is reasonably estimable, or (iii) the probability a loss has been incurred is remote.

Lead pigment litigation

Our former operations included the manufacture of lead pigments for use in paint and lead-based paint. We, other former manufacturers of lead pigments for use in paint and lead-based paint (together, the “former pigment manufacturers”), and the Lead Industries Association (LIA), which discontinued business operations in 2002, have been named as defendants in various legal proceedings seeking damages for personal injury, property damage and governmental expenditures allegedly caused by the use of lead-based paints. Certain of these actions have been filed by or on behalf of states, counties, cities or their public housing authorities and school districts, and certain others have been asserted as class actions. These lawsuits seek recovery under a variety of theories, including public and private nuisance, negligent product design, negligent failure to warn, strict liability, breach of warranty, conspiracy/concert of action, aiding and abetting, enterprise liability, market share or risk contribution liability, intentional tort, fraud and misrepresentation, violations of state consumer protection statutes, supplier negligence and similar claims.

The plaintiffs in these actions generally seek to impose on the defendants responsibility for lead paint abatement and health concerns associated with the use of lead-based paints, including damages for personal injury, contribution and/or indemnification for medical expenses, medical monitoring expenses and costs for educational programs. To the extent the plaintiffs seek compensatory or punitive damages in these actions, such damages are generally unspecified. In some cases, the damages are unspecified pursuant to the requirements of applicable state law. A number of cases are inactive or have been dismissed or withdrawn. Most of the remaining cases are in various pre-trial stages. Some are on appeal following dismissal or summary judgment rulings or a trial verdict in favor of either the defendants or the plaintiffs.

We believe that these actions are without merit, and we intend to continue to deny all allegations of wrongdoing and liability and to defend against all actions vigorously. Other than with respect to the Santa Clara, California public nuisance case discussed below, we do not believe it is probable that we have incurred any liability with respect to all of the lead pigment litigation cases to which we are a party, and with respect to all such lead pigment litigation cases to which we are a party, other than with respect to the Santa Clara case discussed below, we believe liability to us that may result, if any, in this regard cannot be reasonably estimated, because:

•

we have never settled any of the market share, intentional tort, fraud, nuisance, supplier negligence, breach of warranty, conspiracy, misrepresentation, aiding and abetting, enterprise liability, or statutory cases (other than the Santa Clara case discussed below),

•

no final, non-appealable adverse judgments have ever been entered against us, and

•

we have never ultimately been found liable with respect to any such litigation matters, including over 100 cases over a thirty-year period for which we were previously a party and for which we have been dismissed without any finding of liability.

Accordingly, other than with respect to the Santa Clara case discussed below, we have not accrued any amounts for any of the pending lead pigment and lead-based paint litigation cases filed by or on behalf of states, counties, cities or their public housing authorities and school districts, or those asserted as class actions. In addition, we have determined that liability to us which may result, if any, cannot be reasonably estimated at this time because there is no prior history of a loss of this nature on which an estimate could be made and there is no substantive information available upon which an estimate could be based.

In the matter titled County of Santa Clara v. Atlantic Richfield Company, et al. (Superior Court of the State of California, County of Santa Clara, Case No. 1-00-CV-788657) on July 24, 2019, an order approving a global settlement agreement entered into among all of the plaintiffs and the three defendants remaining in the case (the Sherwin Williams Company, ConAgra Grocery Products and us) was entered by the court and the case was dismissed with prejudice. The global settlement agreement provides that an aggregate $305 million will be paid collectively by the three co-defendants in full satisfaction of all claims resulting in a dismissal of the case with prejudice and the resolution of (i) all pending and future claims by the plaintiffs in the case, and (ii) all potential claims for contribution or indemnity between us and our co-defendants in respect to the case. In the agreement, we expressly deny any and all liability and the dismissal of the case with prejudice was entered by the court without a final judgment of liability entered against us. The settlement agreement fully concludes this matter.

Under the terms of the global settlement agreement, each defendant must pay an aggregate $101.7 million to the plaintiffs as follows: $25.0 million within sixty days of the court’s approval of the settlement and dismissal of the case, and the remaining $76.7 million in six annual installments beginning on the first anniversary of the initial payment ($12.0 million for the first five installments and $16.7 million for the sixth installment). Our sixth installment will be made with funds already on deposit at the court that are committed to the settlement, including all accrued interest at the date of payment, with any remaining balance to be paid by us (and any amounts on deposit in excess of the final payment would be returned to us).

As previously disclosed during the second quarter of 2018 and based on the terms of a May 2018 settlement agreement between us and the plaintiffs which had an aggregate cost of $80 million to us, we determined that the loss to us could be reasonably estimated and recognized a net $62 million pre-tax charge with respect to this matter ($45 million for the amount to be paid by us upon approval of the terms of the settlement and $17 million for the net present value of the five payments aggregating $20 million to be paid by us in installments beginning four years from such approval). The May 2018 settlement was never approved by the court and was superseded in July 2019 by the global settlement agreement discussed above.

At June 30, 2019, based on the terms of the global settlement agreement approved by the court in July 2019 we increased the amount accrued for the litigation settlement and a final immaterial adjustment was made to the litigation settlement accrual in the third quarter of 2019. For financial reporting purposes, using a discount rate of 1.9% per annum, we discounted the aggregate $101.7 million settlement to the estimated net present value of $96.3 million. We recognized litigation settlement expense of $19.3 million ($19.6 million expense in the second quarter of 2019 and $.3 million credit in the third quarter of 2019). We made the initial $25.0 million payment in September 2019 and recognized $.3 million in accretion expense during the third quarter of 2019.

For purposes of our Condensed Consolidated Balance Sheet at September 30, 2019, we have recognized the net present value of the $12.0 million payment due in 2020, $11.8 million, as a current liability and the net present value of the five remaining annual installments, $59.8 million, as a noncurrent liability. Under the terms of the settlement, we reclassified the $15.6 million on deposit at the court from an accrued insurance receivable to noncurrent restricted cash at September 30, 2019. Pursuant to the settlement agreement, during the third quarter of 2019 we placed an additional $9.0 million into an escrow account which is included in noncurrent restricted cash on our Condensed Consolidated Balance Sheet.

In November 2018, NL was served with two complaints filed by county governments in Pennsylvania. Each county alleges that NL and several other defendants created a public nuisance by selling and promoting lead-containing paints and pigments in the counties. The plaintiffs seek abatement and declaratory relief. We believe these lawsuits are inconsistent with Pennsylvania law and without merit, and we intend to defend ourselves vigorously.

New cases may continue to be filed against us. We do not know if we will incur liability in the future with respect to any of the pending or possible litigation in view of the inherent uncertainties involved in court and jury rulings. In the future, if new information regarding such matters becomes available to us (such as a final, non-appealable adverse verdict against us or otherwise ultimately being found liable with respect to such matters), at that time we would consider such information in evaluating any remaining cases then-pending against us as to whether it might then have become probable we have incurred liability with respect to these matters, and whether such liability, if any, could have become reasonably estimable. The resolution of any of these cases could result in the recognition of a loss contingency accrual that could have a material adverse impact on our net income for the interim or annual period during which such liability is recognized and a material adverse impact on our consolidated financial condition and liquidity.

Environmental matters and litigation

Our operations are governed by various environmental laws and regulations. Certain of our businesses are and have been engaged in the handling, manufacture or use of substances or compounds that may be considered toxic or hazardous within the meaning of applicable environmental laws and regulations. As with other companies engaged in similar businesses, certain of our past and current operations and products have the potential to cause environmental or other damage. We have implemented and continue to implement various policies and programs in an effort to minimize these risks. Our policy is to maintain compliance with applicable environmental laws and regulations at all of our plants and to strive to improve environmental performance. From time to time, we may be subject to environmental regulatory enforcement under U.S. and non-U.S. statutes, the resolution of which typically involves the establishment of compliance programs. It is possible that future developments, such as stricter requirements of environmental laws and enforcement policies, could adversely affect our production, handling, use, storage, transportation, sale or disposal of such substances. We believe that all of our facilities are in substantial compliance with applicable environmental laws.

Certain properties and facilities used in our former operations, including divested primary and secondary lead smelters and former mining locations, are the subject of civil litigation, administrative proceedings or investigations arising under federal and state environmental laws and common law. Additionally, in connection with past operating practices, we are currently involved as a defendant, potentially responsible party (PRP) or both, pursuant to the Comprehensive Environmental Response, Compensation and Liability Act, as amended by the Superfund Amendments and Reauthorization Act (CERCLA), and similar state laws in various governmental and private actions associated with waste disposal sites, mining locations, and facilities that we or our predecessors, our subsidiaries or their predecessors currently or previously owned, operated or used, certain of which are on the United States Environmental Protection Agency’s (EPA) Superfund National Priorities List or similar state lists. These proceedings seek cleanup costs, damages for personal injury or property damage and/or damages for injury to natural resources. Certain of these proceedings involve claims for substantial amounts. Although we may be jointly and severally liable for these costs, in most cases we are only one of a number of PRPs who may also be jointly and severally liable, and among whom costs may be shared or allocated. In addition, we are occasionally named as a party in a number of personal injury lawsuits filed in various jurisdictions alleging claims related to environmental conditions alleged to have resulted from our operations.

Obligations associated with environmental remediation and related matters are difficult to assess and estimate for numerous reasons including the:

•

complexity and differing interpretations of governmental regulations,

•

number of PRPs and their ability or willingness to fund such allocation of costs,

•

financial capabilities of the PRPs and the allocation of costs among them,

•

solvency of other PRPs,

•

multiplicity of possible solutions,

•

number of years of investigatory, remedial and monitoring activity required,

•

uncertainty over the extent, if any, to which our former operations might have contributed to the conditions allegedly giving rise to such personal injury, property damage, natural resource and related claims, and

•

number of years between former operations and notice of claims and lack of information and documents about the former operations.

In addition, the imposition of more stringent standards or requirements under environmental laws or regulations, new developments or changes regarding site cleanup costs or the allocation of costs among PRPs, solvency of other PRPs, the results of future testing and analysis undertaken with respect to certain sites or a determination that we are potentially responsible for the release of hazardous substances at other sites, could cause our expenditures to exceed our current estimates. We cannot assure you that actual costs will not exceed accrued amounts or the upper end of the range for sites for which estimates have been made, and we cannot assure you that costs will not be incurred for sites where no estimates presently can be made. Further, additional environmental and related matters may arise in the future. If we were to incur any future liability, this could have a material adverse effect on our consolidated financial statements, results of operations and liquidity.

We record liabilities related to environmental remediation and related matters (including costs associated with damages for personal injury or property damage and/or damages for injury to natural resources) when estimated future expenditures are probable and reasonably estimable. We adjust such accruals as further information becomes available to us or as circumstances change. Unless the amounts and timing of such estimated future expenditures are fixed and reasonably determinable, we generally do not discount estimated future expenditures to their present value due to the uncertainty of the timing of the payout. We recognize recoveries of costs from other parties, if any, as assets when their receipt is deemed probable. At December 31, 2018, we had recognized $15.0 million of receivables for recoveries related to the lead pigment litigation in California discussed above.

We do not know and cannot estimate the exact time frame over which we will make payments for our accrued environmental and related costs. The timing of payments depends upon a number of factors, including but not limited to the timing of the actual remediation process; which in turn depends on factors outside of our control. At each balance sheet date, we estimate the amount of our accrued environmental and related costs which we expect to pay within the next twelve months, and we classify this estimate as a current liability. We classify the remaining accrued environmental costs as a noncurrent liability.

Changes in the accrued environmental remediation and related costs during the first nine months of 2019 are as follows:

	Amount
	(In thousands)
Balance at the beginning of the period	$	98,211
Additions charged (credited) to expense, net		(579	)
Payments, net		(2,656	)

Balance at the end of the period	$	94,976

Amounts recognized in the Condensed Consolidated
Balance Sheet at the end of the period:
Current liability	$	3,168
Noncurrent liability		91,808

Balance at the end of the period	$	94,976

On a quarterly basis, we evaluate the potential range of our liability for environmental remediation and related costs at sites where we have been named as a PRP or defendant, including sites for which our wholly-owned environmental management subsidiary, NL Environmental Management Services, Inc. (EMS), has contractually assumed our obligations. At September 30, 2019, we had accrued approximately $95 million related to approximately 32 sites associated with remediation and related matters that we believe are at the present time and/or in their current phase reasonably estimable. The upper end of the range of reasonably possible costs to us for remediation and related matters for which we believe it is possible to estimate costs is approximately $115 million, including the amount currently accrued. These accruals have not been discounted to present value.

We believe that it is not reasonably possible to estimate the range of costs for certain sites. At September 30, 2019, there were approximately five sites for which we are not currently able to reasonably estimate a range of costs. For these sites, generally the investigation is in the early stages, and we are unable to determine whether or not we actually had any association with the site, the nature of our responsibility for the contamination at the site, if any, and the extent of contamination at and cost to remediate the site. The timing and availability of information on these sites is dependent on events outside of our control, such as when the party alleging liability provides information to us. At certain of these previously inactive sites, we have received general and special notices of liability from the EPA and/or state agencies alleging that we, sometimes with other PRPs, are liable for past and future costs of remediating environmental contamination allegedly caused by former operations. These notifications may assert that we, along with any other alleged PRPs, are liable for past and/or future clean-up costs. As further information becomes available to us for any of these sites, which would allow us to estimate a range of costs, we would at that time adjust our accruals. Any such adjustment could result in the recognition of an accrual that would have a material effect on our consolidated financial statements, results of operations and liquidity.

Insurance coverage claims

We are involved in certain legal proceedings with a number of our former insurance carriers regarding the nature and extent of the carriers’ obligations to us under insurance policies with respect to certain lead pigment and asbestos lawsuits. The issue of whether insurance coverage for defense costs or indemnity or both will be found to exist for our lead pigment and asbestos litigation depends upon a variety of factors and we cannot assure you that such insurance coverage will be available.

We have agreements with certain of our former insurance carriers pursuant to which the carriers reimburse us for a portion of our future lead pigment litigation defense costs, and one such carrier reimburses us for a portion of our future asbestos litigation defense costs. We are not able to determine how much we will ultimately recover from these carriers for defense costs incurred by us because of certain issues that arise regarding which defense costs qualify for reimbursement. While we continue to seek additional insurance recoveries, we do not know if we will be successful in obtaining reimbursement for either defense costs or indemnity. Accordingly, we recognize insurance recoveries in income only when receipt of the recovery is probable and we are able to reasonably estimate the amount of the recovery. In this regard we recognized $5.2 million in insurance recoveries in the first nine months of 2019 which represented recovery of past and future litigation defense costs related primarily to a single insurance recovery settlement.

For a complete discussion of certain litigation involving us and certain of our former insurance carriers, refer to our 2018 Annual Report.

Other litigation

In addition to the litigation described above, we and our affiliates are also involved in various other environmental, contractual, product liability, patent (or intellectual property), employment and other claims and disputes incidental to present and former businesses. In certain cases, we have insurance coverage for these items, although we do not expect additional material insurance coverage for environmental matters. We currently believe the disposition of all of these various other claims and disputes, individually and in the aggregate, should not have a material adverse effect on our consolidated financial position, results of operations or liquidity beyond the accruals already provided.

Financial Instruments and Fair Value Measurements

9 Months Ended

Sep. 30, 2019

Fair Value Disclosures [Abstract]

Financial instruments and fair value measurements

Note 15 – Financial instruments and fair value measurements:

See Note 4 for information on how we determine fair value of our marketable securities.

The following table presents the financial instruments that are not carried at fair value but which require fair value disclosure:

	December 31, 2018				September 30, 2019
	Carrying		Fair		Carrying		Fair
	amount		value		amount		value
	(In thousands)
Cash, cash equivalents and restricted cash	$	120,989	$	120,989	$	137,642	$	137,642
Noncontrolling interest in CompX common stock		19,443		22,871		22,377		24,188

The fair value of our noncontrolling interest in CompX stockholders’ equity is based upon its quoted market price at each balance sheet date, which represents a Level 1 input. Due to their near-term maturities, the carrying amounts of accounts receivable and accounts payable are considered equivalent to fair value.

Organization and Basis of Presentation (Policies)	9 Months Ended
Organization and Basis of Presentation (Policies)	Sep. 30, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Organization	Organization – At September 30, 2019, Valhi, Inc. (NYSE: VHI) held approximately 83% of our outstanding common stock and a wholly-owned subsidiary of Contran Corporation (“Contran”) held approximately 92% of Valhi’s outstanding common stock. At September 30, 2019, a majority of Contran’s outstanding voting stock is held directly by Lisa K. Simmons and Serena Simmons Connelly and various family trusts established for the benefit of Ms. Simmons and Ms. Connelly and their children and for which Ms. Simmons or Ms. Connelly, as applicable, serves as trustee. In addition, each of Ms. Simmons and Ms. Connelly serves as co-chair of the Contran board of directors. The remainder of Contran’s outstanding voting stock is held by another trust (the “Family Trust”), which was established for the benefit of Ms. Simmons and Ms. Connelly and their children and for which a third-party financial institution serves as trustee. Consequently, at September 30, 2019, Ms. Simmons, Ms. Connelly and the Family Trust may be deemed to control Contran, and therefore may be deemed to indirectly control the wholly-owned subsidiary of Contran, Valhi and us.
Basis of presentation	Basis of presentation – Consolidated in this Quarterly Report are the results of our majority-owned subsidiary, CompX International Inc. We also own 30% of Kronos Worldwide, Inc. (Kronos). CompX (NYSE American: CIX) and Kronos (NYSE: KRO) each file periodic reports with the Securities and Exchange Commission (SEC). The unaudited Condensed Consolidated Financial Statements contained in this Quarterly Report have been prepared on the same basis as the audited Consolidated Financial Statements in our Annual Report on Form 10-K for the year ended December 31, 2018 that we filed with the SEC on March 11, 2019 (the 2018 Annual Report). In our opinion, we have made all necessary adjustments (which include only normal recurring adjustments) in order to state fairly, in all material respects, our consolidated financial position, results of operations and cash flows as of the dates and for the periods presented. We have condensed the Consolidated Balance Sheet at December 31, 2018 contained in this Quarterly Report as compared to our audited Consolidated Financial Statements at that date, and we have omitted certain information and footnote disclosures (including those related to the Consolidated Balance Sheet at December 31, 2018) normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (GAAP). Our results of operations for the interim periods ended September 30, 2019 may not be indicative of our operating results for the full year. The Condensed Consolidated Financial Statements contained in this Quarterly Report should be read in conjunction with our 2018 Consolidated Financial Statements contained in our 2018 Annual Report. Unless otherwise indicated, references in this report to “NL,” “we,” “us” or “our” refer to NL Industries, Inc. and its subsidiaries and affiliate, Kronos, taken as a whole.

Accounts and Other Receivables, Net (Tables)

9 Months Ended

Sep. 30, 2019

Receivables [Abstract]

Schedule of Accounts Notes Loans and Financing Receivable

	December 31,			September 30,
	2018			2019
	(In thousands)
Trade receivables - CompX	$	12,210		$	13,503
Accrued insurance recoveries		266			289
Other receivables		34			75
Allowance for doubtful accounts		(70	)		(70	)

Total	$	12,440		$	13,797

Inventories, Net (Tables)

9 Months Ended

Sep. 30, 2019

Inventory Disclosure [Abstract]

Schedule of Inventories, Net

	December 31,		September 30,
	2018		2019
	(In thousands)
Raw materials	$	2,661	$	3,313
Work in process		11,130		11,952
Finished products		3,311		3,561

Total	$	17,102	$	18,826

Marketable Securities (Tables)

9 Months Ended

Sep. 30, 2019

Investments Debt And Equity Securities [Abstract]

Schedule of Marketable Securities

	Fair value measurement level	Market value		Cost basis		Unrealized gain
		(In thousands)
December 31, 2018
Valhi common stock	1	$	27,740	$	24,347	$	3,393

September 30, 2019
Valhi common stock	1	$	27,309	$	24,347	$	2,962

Investment in Kronos Worldwide, Inc. (Tables)

9 Months Ended

Sep. 30, 2019

Equity Method Investments And Joint Ventures [Abstract]

Changes in Carrying Value of Investment

The change in the carrying value of our investment in Kronos during the first nine months of 2019 is summarized below.

	Amount
	(In millions)
Balance at the beginning of the period	$	255.5
Equity in earnings of Kronos		23.6
Dividends received from Kronos		(19.0	)
Equity in Kronos' other comprehensive income:
Currency translation		(3.5	)
Defined benefit pension plans		2.0
Equity in Kronos' treasury stock acquired		(.9	)

Balance at the end of the period	$	257.7

Selected Financial Information of Kronos Balance Sheet

Selected financial information of Kronos is summarized below:

	December 31,		September 30,
	2018		2019
	(In millions)
Current assets	$	1,201.4	$	1,186.9
Property and equipment, net		486.4		465.5
Investment in TiO₂ joint venture		81.3		83.1
Other noncurrent assets		129.0		149.4

Total assets	$	1,898.1	$	1,884.9

Current liabilities	$	233.4	$	227.5
Long-term debt		455.1		434.6
Accrued pension costs		262.9		249.3
Other noncurrent liabilities		106.9		126.6
Stockholders' equity		839.8		846.9

Total liabilities and stockholders' equity	$	1,898.1	$	1,884.9

Selected Financial Information of Kronos Income Statement

	Three months ended				Nine months ended
	September 30,				September 30,
	2018		2019		2018		2019
	(In millions)
Net sales	$	410.3	$	437.4	$	1,312.5	$	1,358.4
Cost of sales		291.2		349.7		846.8		1,051.9
Income from operations		58.1		33.1		285.5		128.6
Income tax expense		14.1		6.3		75.5		30.5
Net income		32.6		17.9		181.0		77.7

Other Noncurrent Assets, Net (Tables)

9 Months Ended

Sep. 30, 2019

Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]

Summary of Other Noncurrent Assets

	December 31,		September 30,
	2018		2019
	(In thousands)
Pension asset	$	1,898	$	1,948
Other		1,210		1,239

Total	$	3,108	$	3,187

Accrued and Other Current Liabilities (Tables)

9 Months Ended

Sep. 30, 2019

Payables And Accruals [Abstract]

Schedule of Accrued and Other Current Liabilities

	December 31,		September 30,
	2018		2019
	(In thousands)
Employee benefits	$	9,001	$	7,742
Other		1,853		2,055

Total	$	10,854	$	9,797

Other Noncurrent Liabilities (Tables)

9 Months Ended

Sep. 30, 2019

Other Liabilities Disclosure [Abstract]

Summary of Other Noncurrent Liabilities

	December 31,		September 30,
	2018		2019
	(In thousands)
Reserve for uncertain tax positions	$	7,312	$	7,312
OPEB		1,519		1,409
Insurance claims and expenses		621		621
Other		463		438

Total	$	9,915	$	9,780

Revenue Recognition (Tables)

9 Months Ended

Sep. 30, 2019

Revenue From Contract With Customer [Abstract]

Schedule of Disaggregates Net Sales By Reporting Unit

	Three months ended				Nine months ended
	September 30,				September 30,
	2018		2019		2018		2019
	(In thousands)
Net sales:
Security Products	$	24,541	$	23,405	$	75,845	$	75,036
Marine Components		5,488		6,298		14,982		19,574
Total	$	30,029	$	29,703	$	90,827	$	94,610

Employee Benefit Plans (Tables)

9 Months Ended

Sep. 30, 2019

Defined Benefit Pension Plans

Components of Net Periodic Defined Benefit Cost (Income)

The components of net periodic defined benefit pension cost are presented in the table below.

	Three months ended						Nine months ended
	September 30,						September 30,
	2018			2019			2018			2019
	(In thousands)
Interest cost	$	372		$	474		$	1,116		$	1,422
Expected return on plan assets		(590	)		(477	)		(1,770	)		(1,431	)
Recognized actuarial losses		365			406			1,095			1,218

Total	$	147		$	403		$	441		$	1,209

Income Taxes (Tables)

9 Months Ended

Sep. 30, 2019

Income Tax Disclosure [Abstract]

Component of Income Taxes

	Three months ended						Nine months ended
	September 30,						September 30,
	2018			2019			2018			2019
	(In millions)
Expected tax expense (benefit), at U.S. federal statutory income tax rate of 21%	$	(4.4	)	$	(.7	)	$	(12.1	)	$	4.7
Rate differences on equity in earnings of Kronos		(1.9	)		(1.5	)		(4.3	)		(4.0	)
U.S. state income taxes and other, net		.2			(.1	)		1.0			.2

Income tax expense (benefit)	$	(6.1	)	$	(2.3	)	$	(15.4	)	$	.9

Comprehensive provision for income taxes (benefit) allocable to:
Net income (loss)	$	(6.1	)	$	(2.3	)	$	(15.4	)	$	.9
Additional paid-in capital		-			(.2	)		-			(.2	)
Other comprehensive income (loss):
Currency translation		.3			(1.2	)		(.6	)		(.7	)
Pension plans		.3			.3			.8			.7
OPEB plans		(.1	)		(.1	)		(.1	)		(.1	)

Total	$	(5.6	)	$	(3.5	)	$	(15.3	)	$	.6

Accumulated Other Comprehensive Loss (Tables)

9 Months Ended

Sep. 30, 2019

Stockholders Equity Note [Abstract]

Schedule of Changes in Accumulated Other Comprehensive Loss

Changes in accumulated other comprehensive loss attributable to NL stockholders, including amounts resulting from our investment in Kronos Worldwide (see Note 5), are presented in the table below.

	Three months ended						Nine months ended
	September 30,						September 30,
	2018			2019			2018			2019
	(In thousands)

Accumulated other comprehensive loss, net of tax:
Currency translation:
Balance at beginning of period	$	(167,984	)	$	(170,739	)	$	(164,467	)	$	(172,434	)
Other comprehensive income (loss)		1,103			(4,500	)		(2,414	)		(2,805	)

Balance at end of period	$	(166,881	)	$	(175,239	)	$	(166,881	)	$	(175,239	)

Defined benefit pension plans:
Balance at beginning of period	$	(70,994	)	$	(73,641	)	$	(72,951	)	$	(75,286	)
Other comprehensive income - amortization of net losses included in net periodic pension cost		959			818			2,916			2,463

Balance at end of period	$	(70,035	)	$	(72,823	)	$	(70,035	)	$	(72,823	)

OPEB plans:
Balance at beginning of period	$	(526	)	$	(685	)	$	(388	)	$	(550	)
Other comprehensive loss - amortization of net gains included in net periodic OPEB cost		(65	)		(65	)		(203	)		(200	)

Balance at end of period	$	(591	)	$	(750	)	$	(591	)	$	(750	)

Marketable securities:
Balance at beginning of period	$	-		$	-		$	46,069		$	-
Change in accounting principle		-			-			(46,069	)		-

Balance at end of period	$	-		$	-		$	-		$	-

Total accumulated other comprehensive loss:
Balance at beginning of period	$	(239,504	)	$	(245,065	)	$	(191,737	)	$	(248,270	)
Change in accounting principle		-			-			(46,069	)		-
Balance at beginning of period, as adjusted		(239,504	)		(245,065	)		(237,806	)		(248,270	)
Other comprehensive income (loss)		1,997			(3,747	)		299			(542	)

Balance at end of period	$	(237,507	)	$	(248,812	)	$	(237,507	)	$	(248,812	)

Commitments and Contingencies (Tables)

9 Months Ended

Sep. 30, 2019

Commitments And Contingencies Disclosure [Abstract]

Changes in Accrued Environmental Remediation and Related Costs

Changes in the accrued environmental remediation and related costs during the first nine months of 2019 are as follows:

	Amount
	(In thousands)
Balance at the beginning of the period	$	98,211
Additions charged (credited) to expense, net		(579	)
Payments, net		(2,656	)

Balance at the end of the period	$	94,976

Amounts recognized in the Condensed Consolidated
Balance Sheet at the end of the period:
Current liability	$	3,168
Noncurrent liability		91,808

Balance at the end of the period	$	94,976

Financial Instruments and Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2019

Fair Value Disclosures [Abstract]

Summary of Financial Instruments Not Carried at Fair Value

The following table presents the financial instruments that are not carried at fair value but which require fair value disclosure:

	December 31, 2018				September 30, 2019
	Carrying		Fair		Carrying		Fair
	amount		value		amount		value
	(In thousands)
Cash, cash equivalents and restricted cash	$	120,989	$	120,989	$	137,642	$	137,642
Noncontrolling interest in CompX common stock		19,443		22,871		22,377		24,188

Accounts and Other Receivables, Net - Schedule of Accounts Notes Loans and Financing Receivable (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Receivables [Abstract]
Accrued insurance recoveries	$ 289	$ 266
Other receivables	75	34
Total	13,797	12,440
CompX
Receivables [Abstract]
Trade receivables	13,503	12,210
Allowance for doubtful accounts	$ (70)	$ (70)

Inventories, Net - Schedule of Inventories, Net (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Inventory Disclosure [Abstract]
Raw materials	$ 3,313	$ 2,661
Work in process	11,952	11,130
Finished products	3,561	3,311
Total	$ 18,826	$ 17,102

Marketable Securities - Schedule of Marketable Securities (Detail) - Level 1 - Valhi Inc - Common stock - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Schedule Of Available For Sale Securities [Line Items]
Market value	$ 27,309	$ 27,740
Cost basis	24,347	24,347
Unrealized gain	$ 2,962	$ 3,393

Investment in Kronos Worldwide, Inc. - Additional Information (Detail) - Kronos - USD ($) $ / shares in Units, shares in Millions, $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Schedule Of Equity Method Investments [Line Items]
Number of shares owned	35.2	35.2
Aggregate market value	$ 435.7	$ 405.7
Quoted market price per share	$ 12.37	$ 11.52

Investment in Kronos Worldwide, Inc. - Changes in Carrying Value of Investment (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Balance at the beginning of the period			$ 255,565
Equity in earnings of Kronos Worldwide, Inc.	$ 5,463	$ 9,905	23,632	$ 55,029
Dividends received from Kronos			(19,017)	$ (17,961)
Equity in Kronos' other comprehensive income:
Balance at the end of the period	257,717		257,717
Kronos
Balance at the beginning of the period			255,500
Equity in earnings of Kronos Worldwide, Inc.			23,600
Dividends received from Kronos			(19,000)
Equity in Kronos' other comprehensive income:
Currency translation			(3,500)
Equity in Kronos' treasury stock acquired			(900)
Balance at the end of the period	$ 257,700		257,700
Kronos \| Defined Benefit Pension Plans
Equity in Kronos' other comprehensive income:
Defined benefit pension plans			$ 2,000

Investment in Kronos Worldwide, Inc. - Selected Financial Information of Kronos Balance Sheet (Detail) - Kronos - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Schedule Of Equity Method Investments [Line Items]
Current assets	$ 1,186.9	$ 1,201.4
Property and equipment, net	465.5	486.4
Investment in TiO2 joint venture	83.1	81.3
Other noncurrent assets	149.4	129.0
Total assets	1,884.9	1,898.1
Current liabilities	227.5	233.4
Long-term debt	434.6	455.1
Accrued pension costs	249.3	262.9
Other noncurrent liabilities	126.6	106.9
Stockholders' equity	846.9	839.8
Total liabilities and stockholders' equity	$ 1,884.9	$ 1,898.1

Investment in Kronos Worldwide, Inc. - Selected Financial Information of Kronos Income Statement (Detail) - Kronos - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Schedule Of Equity Method Investments [Line Items]
Net sales	$ 437.4	$ 410.3	$ 1,358.4	$ 1,312.5
Cost of sales	349.7	291.2	1,051.9	846.8
Income from operations	33.1	58.1	128.6	285.5
Income tax expense	6.3	14.1	30.5	75.5
Net income	$ 17.9	$ 32.6	$ 77.7	$ 181.0

Other Noncurrent Assets, Net - Summary of Other Noncurrent Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Pension asset	$ 1,948	$ 1,898
Other	1,239	1,210
Total	$ 3,187	$ 3,108

Accrued and Other Current Liabilities - Schedule of Accrued and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Payables And Accruals [Abstract]
Employee benefits	$ 7,742	$ 9,001
Other	2,055	1,853
Total	$ 9,797	$ 10,854

Long-Term Debt - Additional Information (Detail) - NLKW Holding, LLC - Valhi - Valhi Credit Facility	9 Months Ended
	Sep. 30, 2019 USD ($)
Debt Instrument [Line Items]
Maximum borrowing under credit facility	$ 50,000,000
Borrowings or repayments under revolving credit facility	0
Outstanding borrowing	500,000
Remaining future borrowing under revolving credit facility	$ 49,500,000
Debt instrument, description of variable rate basis	prime rate
Variable rate basis spread above reference rate	1.875%
Debt instrument average interest rate	6.90%
Debt instrument interest rate	7.30%

Other Noncurrent Liabilities - Summary of Other Noncurrent Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Other Liabilities Disclosure [Abstract]
Reserve for uncertain tax positions	$ 7,312	$ 7,312
OPEB	1,409	1,519
Insurance claims and expenses	621	621
Other	438	463
Total	$ 9,780	$ 9,915

Employee Benefit Plans - Components of Net Periodic Defined Benefit Cost (Income) (Detail) - Defined Benefit Pension Plans - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 474	$ 372	$ 1,422	$ 1,116
Expected return on plan assets	(477)	(590)	(1,431)	(1,770)
Recognized actuarial losses	406	365	1,218	1,095
Total	$ 403	$ 147	$ 1,209	$ 441

Income Taxes - Component of Income Taxes (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Expected tax expense (benefit), at U.S. federal statutory income tax rate of 21%	$ (700)	$ (4,400)	$ 4,700	$ (12,100)
Rate differences on equity in earnings of Kronos	(1,500)	(1,900)	(4,000)	(4,300)
U.S. state income taxes and other, net	(100)	200	200	1,000
Income tax expense (benefit)	$ (2,286)	$ (6,158)	$ 942	$ (15,416)

Income Taxes - Components of Comprehensive Provision for Income Taxes Allocation (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Comprehensive provision for income taxes (benefit) allocable to:
Net income (loss)	$ (2,286)	$ (6,158)	$ 942	$ (15,416)
Additional paid-in capital	(200)		(200)
Other comprehensive income (loss):
Currency translation	(1,200)	300	(700)	(600)
Total	(3,500)	(5,600)	600	(15,300)
OPEB
Other comprehensive income (loss):
Defined benefit plans	(100)	(100)	(100)	(100)
Defined Benefit Pension Plans
Other comprehensive income (loss):
Defined benefit plans	$ 300	$ 300	$ 700	$ 800

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Income Tax Disclosure [Line Items]
Dividends received from Kronos Worldwide, Inc.		$ 19,017	$ 17,961
Kronos
Income Tax Disclosure [Line Items]
Dividends received from Kronos Worldwide, Inc.		$ 19,000	$ 18,000
Kronos German Subsidiary \| Canada - Germany APA \| Germany Revenue Agency \| Earliest Tax Year
Income Tax Disclosure [Line Items]
Effective tax year	2005
Kronos German Subsidiary \| Canada - Germany APA \| Germany Revenue Agency \| Latest Tax Year
Income Tax Disclosure [Line Items]
Effective tax year	2017
Kronos Canadian And German Subsidiaries \| Canada - Germany APA
Income Tax Disclosure [Line Items]
Non-cash income tax benefit	$ 1,400

Accumulated Other Comprehensive Loss - Schedule of Changes in Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period			$ 284,115
Balance at end of period	$ 301,084		301,084
Currency Translation
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(170,739)	$ (167,984)	(172,434)	$ (164,467)
Other comprehensive income (loss)	(4,500)	1,103	(2,805)	(2,414)
Balance at end of period	(175,239)	(166,881)	(175,239)	(166,881)
Accumulated Defined Benefit Plans Adjustment \| Defined Benefit Pension Plans
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(73,641)	(70,994)	(75,286)	(72,951)
Other comprehensive income (loss)	818	959	2,463	2,916
Balance at end of period	(72,823)	(70,035)	(72,823)	(70,035)
Accumulated Defined Benefit Plans Adjustment \| OPEB
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(685)	(526)	(550)	(388)
Other comprehensive income (loss)	(65)	(65)	(200)	(203)
Balance at end of period	(750)	(591)	(750)	(591)
Marketable Securities
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period				46,069
Change in accounting principle - ASU 2016-01				(46,069)
Accumulated other comprehensive income (loss)
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	(245,065)	(239,504)	(248,270)	(191,737)
Change in accounting principle - ASU 2016-01				(46,069)
Balance at beginning of period, as adjusted	(245,065)	(239,504)	(248,270)	(237,806)
Other comprehensive income (loss)	(3,747)	1,997	(542)	299
Balance at end of period	$ (248,812)	$ (237,507)	$ (248,812)	$ (237,507)

Commitments and Contingencies - Additional Information (Detail)		1 Months Ended	3 Months Ended				9 Months Ended
	Jul. 24, 2019 USD ($) Defendant Installment	Nov. 30, 2018 Cases	Sep. 30, 2019 USD ($) Installment site	Jun. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($) Installment	Sep. 30, 2019 USD ($) Cases Installment site	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Commitments and Contingent Liabilities [Line Items]
Litigation settlement net present value			$ 59,797,000				$ 59,797,000		$ 17,000,000
Litigation settlement expense			(305,000)				19,266,000	$ 62,000,000
Litigation settlement			11,774,000				11,774,000		60,000,000
Number of complaints filed \| Cases		2
Accrual for reasonably estimable environmental remediation and related matters			94,976,000				94,976,000		98,211,000
Insurance recoveries			243,000		$ 526,000		5,240,000	$ 889,000
Environmental Remediation Sites NL Named As PRP Or Defendant
Commitments and Contingent Liabilities [Line Items]
Accrual for reasonably estimable environmental remediation and related matters			$ 95,000,000				$ 95,000,000
Number of sites associated with remediation and related costs \| site			32				32
Number of sites currently not able to reasonably estimate a range of costs \| site			5				5
Maximum \| Environmental Remediation Sites NL Named As PRP Or Defendant
Commitments and Contingent Liabilities [Line Items]
Upper end range, estimate costs for remediation and related matters			$ 115,000,000				$ 115,000,000
Environmental Remediation Litigation
Commitments and Contingent Liabilities [Line Items]
Recoveries receivable									$ 15,000,000
Lead Pigment Litigation
Commitments and Contingent Liabilities [Line Items]
Number of cases settled and dismissed and found not liable \| Cases							100
Period by which loss contingency claims settled and dismissed							30 years
Description of defendants							on July 24, 2019, an order approving a global settlement agreement entered into among all of the plaintiffs and the three defendants remaining in the case (the Sherwin Williams Company, ConAgra Grocery Products and us) was entered by the court and the case was dismissed with prejudice. The global settlement agreement provides that an aggregate $305 million will be paid collectively by the three co-defendants in full satisfaction of all claims resulting in a dismissal of the case with prejudice and the resolution of (i) all pending and future claims by the plaintiffs in the case, and (ii) all potential claims for contribution or indemnity between us and our co-defendants in respect to the case.
Number of defendants \| Defendant	3
Litigation settlement amount	$ 305,000,000
NL's portion of global settlement amount, gross value	101,700,000					$ 62,000,000
Litigation initial payment made 60 days after litigation settlement	25,000,000
Remaining litigation settlement charge	$ 76,700,000					$ 20,000,000
Number of annual installments \| Installment	6		5			5	5
Remaining litigation settlement payment due in first year	$ 12,000,000
Remaining litigation settlement payment due in second year	12,000,000
Remaining litigation settlement payment due in third year	12,000,000
Remaining litigation settlement payment due in fourth year	12,000,000
Remaining litigation settlement payment due in fifth year	12,000,000
Remaining litigation settlement payment due in sixth year	$ 16,700,000
Litigation settlement, current						$ 80,000,000
Litigation settlement charge upon approval of settlement terms						45,000,000
Litigation settlement net present value						$ 17,000,000
Litigation settlement installments payment beginning term from approval						4 years
Discounted rate for estimated present value of remaining litigation amount			1.90%				1.90%
Litigation settlement estimated net present value			$ 96,300,000				$ 96,300,000
Litigation settlement expense				$ 19,600,000			19,300,000
Litigation settlement credit			300,000
Litigation initial payment			25,000,000
Recognized accretion expense			300,000
Litigation payment due			12,000,000				12,000,000
Noncurrent restricted cash			15,600,000				15,600,000
Escrow deposit			$ 9,000,000				$ 9,000,000

Commitments and Contingencies - Changes in Accrued Environmental Remediation and Related Costs (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Dec. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Balance at the beginning of the period	$ 98,211
Additions charged (credited) to expense, net	(579)
Payments, net	(2,656)
Balance at the end of the period	94,976
Amounts recognized in the Condensed Consolidated Balance Sheet at the end of the period:
Current liability	3,168	$ 5,027
Noncurrent liability	$ 91,808	$ 93,184

Financial Instruments and Fair Value Measurements - Summary of Financial Instruments Not Carried at Fair Value (Detail) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash, cash equivalents and restricted cash, Fair value	$ 137,642	$ 120,989
Noncontrolling interest in subsidiary	22,377	19,443
Carrying Amount
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash, cash equivalents and restricted cash, Carrying amount	137,642	120,989
Carrying Amount \| CompX
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Noncontrolling interest in subsidiary	22,377	19,443
Fair Value \| CompX
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Noncontrolling interest in subsidiary	$ 24,188	$ 22,871

Organization and Basis of Presentation - Additional Information (Detail)	Sep. 30, 2019
Kronos
Organization And Basis Of Presentation [Line Items]
Parent company ownership interest	30.00%
Parent Company \| Valhi Inc
Organization And Basis Of Presentation [Line Items]
Parent company ownership interest	83.00%
Parent Company \| Contran Corporation
Organization And Basis Of Presentation [Line Items]
Parent company ownership interest	92.00%

Marketable Securities - Additional Information (Detail) - Valhi Inc - Common stock - $ / shares shares in Millions	Sep. 30, 2019	Dec. 31, 2018
Schedule Of Available For Sale Securities [Line Items]
Number of shares owned	14.4	14.4
Quoted marked price per share	$ 1.90	$ 1.93

Employee Benefit Plans - Additional Information (Detail) $ in Millions	Sep. 30, 2019 USD ($)
Defined Benefit Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Expected contribution during 2019	$ 3.3

Income Taxes - Component of Income Taxes (Parenthetical) (Detail)	9 Months Ended
	Sep. 30, 2019
Income Tax Disclosure [Abstract]
U.S. federal statutory income tax rate	21.00%