Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net (loss) income	$ (14,793)	$ 1,389
Adjustments for changes in:
Foreign currency translation	449	2,498
Unrecognized employee benefit costs (including effects of foreign currency translation)	4,149	(413)
Fair value of cash flow hedges	268	(315)
Reclassification adjustments for items included in net (loss) income:
Amortization of unrecognized employee benefit costs	161	130
Realized losses (gains) from settlement of cash flow hedges	119	(209)
Other comprehensive income	5,146	1,691
Comprehensive (loss) income	(9,647)	3,080
Less: Comprehensive income attributable to noncontrolling interest	488	599
Comprehensive (loss) income attributable to Ampco-Pittsburgh	$ (10,135)	$ 2,481

Other comprehensive income loss gross adjustments net of tax.

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