CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Net income (loss)	$ 6,560	$ (41,962)	$ 22,286	$ (27,226)
Other comprehensive income (loss), net of tax:
Currency translation	1,720	(6,108)	1,695	(3,517)
Total other comprehensive income (loss), net	2,472	(5,199)	3,205	(1,698)
Comprehensive income (loss)	9,032	(47,161)	25,491	(28,924)
Comprehensive income attributable to noncontrolling interest	682	653	1,204	1,140
Comprehensive income (loss) attributable to NL stockholders	8,350	(47,814)	24,287	(30,064)
Defined Benefit Pension Plans
Other comprehensive income (loss), net of tax:
Defined benefit plans	817	974	1,645	1,957
Other Postretirement Benefit Plans
Other comprehensive income (loss), net of tax:
Defined benefit plans	$ (65)	$ (65)	$ (135)	$ (138)

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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