CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
CONSOLIDATED STATEMENTS OF OPERATIONS
Net sales	$ 145,941	$ 161,287	$ 166,562
Cost of sales	104,578	112,068	117,763
Gross margin	41,363	49,219	48,799
Selling, general and administrative expense	24,340	23,784	23,363
Other operating income (expense):
Insurance recoveries	1,369	464	93
Corporate income (expenses), net	19,484	(11,770)	(11,798)
Income from operations	37,876	14,129	13,731
Equity in earnings (losses) of Kronos Worldwide, Inc.	26,381	(15,003)	31,873
Other income (expense):
Interest and dividend income	10,980	9,636	3,797
Marketable equity securities	9,821	(8,156)	(8,085)
Loss on pension plan termination		(4,911)
Other components of net periodic pension and OPEB cost	(1,210)	(1,368)	(1,134)
Interest expense	(530)	(746)	(941)
Income (loss) before income taxes	83,318	(6,419)	39,241
Income tax expense (benefit)	14,057	(7,001)	2,785
Net income	69,261	582	36,456
Noncontrolling interest in net income of subsidiary	2,033	2,890	2,612
Net income (loss) attributable to NL stockholders	$ 67,228	$ (2,308)	$ 33,844
Amounts attributable to NL stockholders:
Net income (loss) per basic share	$ 1.38	$ (0.05)	$ 0.69
Net income (loss) per diluted share	$ 1.38	$ (0.05)	$ 0.69
Weighted average shares outstanding - basic	48,842	48,827	48,811
Weighted average shares outstanding - diluted	48,842	48,827	48,811