CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Net income	$ 2,502	$ 15,726
Other comprehensive income (loss), net of tax:
Currency translation	(10,118)	(25)
Total other comprehensive income (loss), net	(9,155)	733
Comprehensive income (loss)	(6,653)	16,459
Comprehensive income attributable to noncontrolling interest	592	522
Comprehensive income (loss) attributable to NL stockholders	(7,245)	15,937
Defined Benefit Pension Plans
Other comprehensive income (loss), net of tax:
Defined benefit plans	1,043	828
Other Postretirement Benefit Plans
Other comprehensive income (loss), net of tax:
Defined benefit plans	$ (80)	$ (70)