Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
Net sales	$ 115,077	$ 103,516
Operating costs and expenses:
Costs of products sold (excluding depreciation and amortization)	94,757	84,781
Selling and administrative	15,473	15,377
Depreciation and amortization	5,905	5,922
Loss on disposition of assets	45	0
Total operating expenses	116,180	106,080
Loss from operations	(1,103)	(2,564)
Other income (expense):
Investment-related income	24	49
Interest expense	(873)	(1,177)
Other – net	2,900	(885)
Total other income (expense)	2,051	(2,013)
Income (loss) before income taxes and equity income in joint venture	948	(4,577)
Income tax benefit (provision)	441	(135)
Equity income in joint venture	0	50
Net income (loss)	1,389	(4,662)
Less: Net income attributable to noncontrolling interest	448	121
Net income (loss) attributable to Ampco-Pittsburgh shareholders	$ 941	$ (4,783)
Net income (loss) per common share attributable to Ampco-Pittsburgh:
Basic	$ 0.08	$ (0.39)
Diluted	0.08	(0.39)
Cash dividends declared per share	$ 0.00	$ 0.09
Weighted average number of common shares outstanding:
Basic	12,362	12,271
Diluted	12,379	12,271