CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Net income (loss)	$ (41,962)	$ 41,598	$ (27,226)	$ 50,360
Other comprehensive income (loss), net of tax:
Marketable securities		(2,869)		(4,591)
Currency translation	(6,108)	2,925	(3,517)	4,696
Interest rate swap		(84)		28
Total other comprehensive income (loss), net	(5,199)	317	(1,698)	1,297
Comprehensive income (loss)	(47,161)	41,915	(28,924)	51,657
Comprehensive income attributable to noncontrolling interest	653	431	1,140	843
Comprehensive income (loss) attributable to NL stockholders	(47,814)	41,484	(30,064)	50,814
Defined Benefit Pension Plans
Other comprehensive income (loss), net of tax:
Defined benefit pension plans/ Other postretirement benefit plans	974	393	1,957	1,260
OPEB
Other comprehensive income (loss), net of tax:
Defined benefit pension plans/ Other postretirement benefit plans	$ (65)	$ (48)	$ (138)	$ (96)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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