CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
CONDENSED CONSOLIDATED STATEMENTS OF INCOME
Net sales	$ 36,616	$ 41,675	$ 77,767	$ 83,725
Cost of sales	26,343	28,046	54,790	58,016
Gross margin	10,273	13,629	22,977	25,709
Selling, general and administrative expense	5,906	5,884	11,570	11,658
Other operating income (expense):
Corporate expense	2,946	3,540	5,789	5,976
Income from operations	1,421	4,205	5,618	8,075
Equity in earnings (losses) of Kronos Worldwide, Inc.	(2,516)	13,991	(7,153)	31,524
Other income (expense):
Interest and dividend income	2,145	567	4,110	876
Marketable equity securities	(5,461)	19,200	(10,959)	19,871
Loss on pension plan termination	(4,911)		(4,911)
Other components of net periodic pension and OPEB cost	(370)	(223)	(716)	(446)
Interest expense	(199)	(248)	(398)	(494)
Income (loss) before income taxes	(9,891)	37,492	(14,409)	59,406
Income tax expense (benefit)	(7,300)	6,435	(5,879)	9,140
Net income (loss)	(2,591)	31,057	(8,530)	50,266
Noncontrolling interest in net income of subsidiary	517	805	1,294	1,457
Net income (loss) attributable to NL stockholders	$ (3,108)	$ 30,252	$ (9,824)	$ 48,809
Amounts attributable to NL stockholders:
Net income (loss) per basic share	$ (0.06)	$ 0.62	$ (0.20)	$ 1.00
Net income (loss) per diluted share	$ (0.06)	$ 0.62	$ (0.20)	$ 1.00
Weighted average shares outstanding - basic	48,824	48,809	48,820	48,806
Weighted average shares outstanding - diluted	48,824	48,809	48,820	48,806