CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
CONSOLIDATED STATEMENTS OF OPERATIONS
Net sales	$ 158,285	$ 145,941	$ 161,287
Cost of sales	110,106	104,578	112,068
Gross margin	48,179	41,363	49,219
Selling, general and administrative expense	25,575	24,340	23,784
Other operating income (expense):
Insurance recoveries		1,369	464
Corporate income (expense), net	11,929	(19,484)	11,770
Income from operations	10,675	37,876	14,129
Equity in earnings (losses) of Kronos Worldwide, Inc.	(33,940)	26,381	(15,003)
Other income (expense):
Interest and dividend income	7,000	10,980	9,636
Marketable equity securities	(13,582)	9,821	(8,156)
Settlement loss on pension plan termination and buy-out	(19,670)		(4,911)
Other components of net periodic pension and OPEB cost	(1,140)	(1,210)	(1,368)
Interest expense	(767)	(530)	(746)
Income (loss) before income taxes	(51,424)	83,318	(6,419)
Income tax expense (benefit)	(16,053)	14,057	(7,001)
Net income (loss)	(35,371)	69,261	582
Noncontrolling interest in net income of subsidiary	2,455	2,033	2,890
Net income (loss) attributable to NL stockholders	$ (37,826)	$ 67,228	$ (2,308)
Amounts attributable to NL stockholders:
Basic net income (loss) per share	$ (0.77)	$ 1.38	$ (0.05)
Diluted net income (loss) per share	$ (0.77)	$ 1.38	$ (0.05)
Weighted average shares used in the calculation of net income (loss) per share - basic	48,857	48,842	48,827
Weighted average shares used in the calculation of net income (loss) per share - diluted	48,857	48,842	48,827