Mortgage Servicing Rights and Mortgage Servicing Liabilities - Mortgage Servicing Liabilities Carried at FV (Details) - Mortgage servicing liabilities - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Amortized cost:
Balance at beginning of quarter	$ 1,805	$ 2,096
Changes in valuation inputs used in valuation model	(27)	(15)
Other changes in fair value	(46)	(70)
Total change in fair value	(73)	(85)
Balance at end of quarter	1,732	2,011
UPB of underlying loan at end of quarter	$ 22,644	$ 28,380

The unpaid principal balance (UPB) of underlying loan.

No definition available.

Name:	pfsi_UnpaidPrincipalBalanceOfUnderlyingLoan
Namespace Prefix:	pfsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value of a liability representing servicing arrangements under which the estimated future revenue from contractually specified servicing fees, late charges, and other ancillary revenues are not expected to adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481260/860-50-45-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481260/860-50-45-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481260/860-50-45-2

+ Details

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

- Definition

Amount of increase (decrease) in fair value from changes in the inputs, assumptions, or model used to calculate the fair value of the contract to service financial assets under which the estimated future revenues from contractually specified servicing fees, late charges, and other ancillary revenues are not expected to adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(4)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-3

+ Details

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

- Definition

Amount of increase (decrease) from changes in fair value classified as other for a contract to service financial assets under which the estimated future revenues from contractually specified servicing fees, late charges, and other ancillary revenues are not expected to adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(4)(ii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-3

+ Details

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

- Definition

The net increase (decrease) in the fair value of servicing liabilities subsequently measured at fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-3

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_FinancialInstrumentAxis=pfsi_MortgageServicingLiabilitiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: