Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Statement of Comprehensive Income [Abstract]
Net loss	$ (4,662)	$ (2,974)
Adjustments for changes in:
Foreign currency translation	2,252	(315)
Unrecognized employee benefit costs (including effects of foreign currency translation)	(255)	649
Unrealized holding gains on marketable securities	185	148
Fair value of cash flow hedges	224	18
Reclassification adjustments for items included in net loss:
Amortization of unrecognized employee benefit costs	733	785
Realized gains on sale of marketable securities	(6)	(30)
Realized gains/losses from settlement of cash flow hedges	(155)	135
Other comprehensive income	2,978	1,390
Comprehensive loss	(1,684)	(1,584)
Less: Comprehensive income (loss) attributable to noncontrolling interest	124	(83)
Comprehensive loss attributable to Ampco-Pittsburgh	$ (1,808)	$ (1,501)

Other comprehensive income loss gross adjustments net of tax.

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