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, 2023	Dec. 31, 2022
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Depreciation and amortization (foreign currency purchase contracts)	$ (17,674)	$ (17,408)
Costs of products sold (excluding depreciation and amortization) (futures contracts - copper and aluminum)	(347,781)	(327,996)
(Loss) income before income taxes	(39,277)	5,556
Other – net	4,516	7,693
Income tax provision	1,158	(1,576)
Net (loss) income attributable to Ampco-Pittsburgh	(39,928)	3,416
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	(891)	1,116
Income tax provision		(1)
Net (loss) income attributable to Ampco-Pittsburgh	(891)	1,115
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)	59	426
(Loss) income before income taxes	32	399
Income tax provision	(2)	(12)
Net (loss) income attributable to Ampco-Pittsburgh	$ 30	$ 387