CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Net income (loss)	$ (2,181)	$ 10,357
Other comprehensive income (loss), net of tax:
Marketable securities	(1,531)	(1,786)
Currency translation	2,831	(12,959)
Interest rate swap	(571)
Total other comprehensive income (loss), net	1,404	(14,147)
Comprehensive loss	(777)	(3,790)
Comprehensive income attributable to noncontrolling interest	288	315
Comprehensive loss attributable to NL stockholders	(1,065)	(4,105)
Defined Benefit Pension Plans
Other comprehensive income (loss), net of tax:
Defined benefit pension plans/ Other postretirement benefit plans	807	734
OPEB
Other comprehensive income (loss), net of tax:
Defined benefit pension plans/ Other postretirement benefit plans	$ (132)	$ (136)