Boolean flag that is true when the XBRL content amends previously-filed or accepted submission.

No definition available.

Name:	dei_AmendmentFlag
Namespace Prefix:	dei_
Data Type:	xbrli:booleanItemType
Balance Type:	na
Period Type:	duration

- Definition

PCAOB issued Audit Firm Identifier

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form 10-K
-Number 249
-Section 310

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form 20-F
-Number 249
-Section 220
-Subsection f

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Form 40-F
-Number 249
-Section 240
-Subsection f

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2024	Mar. 13, 2025	Jun. 30, 2024
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2024
Document Fiscal Year Focus	2024
Document Annual Report	true
Document Transition Report	false
Document Fiscal Period Focus	FY
Entity Registrant Name	AMPCO-PITTSBURGH CORP
Entity Central Index Key	0000006176
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		20,094,617
Entity Public Float			$ 9
Entity Incorporation, State or Country Code	PA
Entity Tax Identification Number	25-1117717
Entity Address, Address Line One	726 Bell Avenue
Entity Address, Address Line Two	Suite 301
Entity Address, City or Town	Carnegie
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	15106
City Area Code	412
Local Phone Number	456-4400
Entity Interactive Data Current	Yes
Entity File Number	1-898
Documents Incorporated by Reference	Documents Incorporated by Reference: Part III of this report incorporates by reference certain information from the Proxy Statement for the 2025 Annual Meeting of Shareholders.
Auditor Opinion [Text Block]	Opinion on the Consolidated Financial Statements We have audited the accompanying consolidated balance sheets of Ampco-Pittsburgh Corporation (the Corporation) as of December 31, 2024 and 2023, the related consolidated statements of operations, comprehensive loss, shareholders’ equity, and cash flows for each of the years then ended, and the related notes (collectively referred to as the “consolidated financial statements”). In our opinion, the consolidated financial statements present fairly, in all material respects, the financial position of the Corporation at December 31, 2024 and 2023, and the results of its operations and its cash flows for each of the years then ended, in conformity with accounting principles generally accepted in the United States of America.
Auditor Name	BDO USA, P.C.
Auditor Location	Pittsburgh, Pennsylvania
Auditor Firm ID	243
Common Stock [Member]
Document Information [Line Items]
Trading Symbol	AP
Title of 12(b) Security	Common Stock, $1 par value
Security Exchange Name	NYSE
Series A Warrants [Member]
Document Information [Line Items]
Trading Symbol	AP WS
Title of 12(b) Security	Series A Warrants to purchase shares of Common Stock
Security Exchange Name	NYSEAMER