CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Net income (loss)	$ 8,762	$ (2,181)
Other comprehensive income (loss), net of tax:
Marketable securities	(1,722)	(1,531)
Currency translation	1,771	2,831
Interest rate swap	112	(571)
Total other comprehensive income (loss), net	980	1,404
Comprehensive income (loss)	9,742	(777)
Comprehensive income attributable to noncontrolling interest	412	288
Comprehensive income (loss) attributable to NL stockholders	9,330	(1,065)
Defined Benefit Pension Plans
Other comprehensive income (loss), net of tax:
Defined benefit pension plans/ Other postretirement benefit plans	867	807
OPEB
Other comprehensive income (loss), net of tax:
Defined benefit pension plans/ Other postretirement benefit plans	$ (48)	$ (132)