Accumulated Other Comprehensive Loss - Line Items Affected on Consolidated Statements of Operations for Components Reclassified from Accumulated Other Comprehensive Loss (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Depreciation and amortization (foreign currency purchase contracts)	$ (17,408)	$ (17,877)	[1],[2]
Costs of products sold (excluding depreciation and amortization) (futures contracts - copper and aluminum)	(327,996)	(278,805)	[1]
Income (loss) before income taxes	5,556	(995)	[1]
Other – net	7,693	6,302	[1]
Income tax (provision) benefit	(1,576)	(2,305)	[1]
Net income attributable to Ampco-Pittsburgh	3,416	(3,861)	[1]
Amortization of Unrecognized Employee Benefit Costs [Member] | Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Other – net	1,116	1,876
Income tax (provision) benefit	(1)	(50)
Net income attributable to Ampco-Pittsburgh	1,115	1,826
Derivatives [Member] | Reclassification Out of Accumulated Other Comprehensive Income (Loss) [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Depreciation and amortization (foreign currency purchase contracts)	(27)	(27)
Costs of products sold (excluding depreciation and amortization) (futures contracts - copper and aluminum)	426	(1,092)
Income (loss) before income taxes	399	(1,119)
Income tax (provision) benefit	(12)	33
Net income attributable to Ampco-Pittsburgh	$ 387	$ (1,086)

[1] Costs of products sold (excluding depreciation and amortization) and subsequent subtotals and totals along with net loss per share for 2021 were adjusted to include inventory costs using the FIFO basis of costing. See Note 2.

[2] Net loss and the change in inventories for 2021 were adjusted to include inventory costs using the FIFO basis of costing. See Note 2.   See Notes to Consolidated Financial Statements.