CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Net income (loss)	$ 5,806	$ (14,018)	$ 9,840	$ (16,016)
Other comprehensive income (loss), net of tax:
Marketable securities	(22,933)	(22,075)	(106,864)	11,826
Currency translation	(860)	1,116	(1,374)	(4,274)
Total other comprehensive income (loss)	(23,431)	(20,416)	(107,496)	8,650
Comprehensive loss	(17,625)	(34,434)	(97,656)	(7,366)
Comprehensive income attributable to noncontrolling interest	334	237	613	357
Comprehensive loss attributable to NL stockholders	(17,959)	(34,671)	(98,269)	(7,723)
Defined Benefit Pension Plans
Other comprehensive income (loss), net of tax:
Defined benefit pension plans/ Other postretirement benefit plans	518	687	1,055	1,386
OPEB
Other comprehensive income (loss), net of tax:
Defined benefit pension plans/ Other postretirement benefit plans	$ (156)	$ (144)	$ (313)	$ (288)