Commitments and Contingent Liabilities - Additional Information (Detail) - 3 months ended Mar. 31, 2021 kr in Thousands, $ in Thousands	USD ($)	SEK (kr)
Commitments And Contingent Liabilities [Line Items]
Outstanding standby and commercial letters of credit	$ 14,352
Surety bonds issued to guarantee obligations	4,000	kr 33,900
Capital Expenditures [Member]
Commitments And Contingent Liabilities [Line Items]
Purchase commitments	$ 3,700
Capital Expenditures [Member] \| Minimum [Member]
Commitments And Contingent Liabilities [Line Items]
Purchase commitments, period	12 months
Capital Expenditures [Member] \| Maximum [Member]
Commitments And Contingent Liabilities [Line Items]
Purchase commitments, period	18 months

Commitments And Contingent Liabilities [Line Items]

No definition available.

Name:	ap_CommitmentsAndContingentLiabilitiesLineItems
Namespace Prefix:	ap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Sum of the amount of expected guaranteed benefits in excess of the projected account balances for minimum guaranteed benefit contracts, as of the balance sheet date, net of reinsurance recoverables, for all guaranteed benefit types.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section 55
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=121639652&loc=d3e7104-158389

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 80
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121641442&loc=d3e19393-158473

+ Details

Name:	us-gaap_GuaranteedBenefitLiabilityNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermPurchaseCommitmentAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Period covered by the long-term purchase commitment, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Details

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- Details

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- Details

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