CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 582	$ 36,456	$ 53,360
Other comprehensive income (loss), net of tax:
Currency translation	1,072	(6,956)	(1,660)
Defined benefit pension plans	2,484	24,611	12,236
Marketable debt securities	53	(50)
Other postretirement benefit plans	(221)	160	(143)
Total other comprehensive income, net	3,388	17,765	10,433
Comprehensive income	3,970	54,221	63,793
Comprehensive income attributable to noncontrolling interest	2,908	2,612	2,172
Comprehensive income attributable to NL stockholders	$ 1,062	$ 51,609	$ 61,621