Represents the amount pertaining to excess servicing spread recapture recognized during the period.

No definition available.

Name:	pfsi_ExcessServicingSpreadFinancingRecaptureRecognized
Namespace Prefix:	pfsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the amount up to which PFSI may repay PMT in cash to settle its ESS recapture obligation in place of issuing new ESS.

+ References

No definition available.

+ Details

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Namespace Prefix:	pfsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Represents the cash outflow from repayment of excess servicing spread financing.

+ References

No definition available.

+ Details

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Namespace Prefix:	pfsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents ESS issued to related party under an agreement to replace ESS reductions arising from the Company's refinances any of the mortgage loans relating to the ESS it sells to related party, at no cost, the ESS relating to a certain percentage of the UPB of the newly originated mortgage loans.

+ References

No definition available.

+ Details

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Namespace Prefix:	pfsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

+ Details

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

- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
-Section 50
-Paragraph 2
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
-Section 50
-Paragraph 1
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

+ Details

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

- References

No definition available.

+ Details

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

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- Details

Name:	us-gaap_RelatedPartyTransactionAxis=pfsi_FirstMasterSpreadAcquisitionAndMortgageServicingRightsServicingAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByLiabilityClassAxis=pfsi_ExcessServicingSpreadFinancingMember
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Related Party Transactions - Financing Activities (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Feb. 01, 2013
Financing activities:
Issuance pursuant to recapture agreement				$ 557,000
Interest Expense	$ 71,127,000	$ 102,431,000	$ 148,434,000	210,144,000
Repayments				134,624,000
Change in fair value				(1,037,000)
PennyMac Mortgage Investment Trust
Financing activities:
Interest Expense				1,280,000
PennyMac Mortgage Investment Trust \| 2/1/13 Spread Acquisition Agreement
Financing activities:
Maximum ESS recapture obligation					$ 200,000
Excess servicing spread financing \| PennyMac Mortgage Investment Trust
Financing activities:
Balance at the beginning of the period				131,750,000
Issuance pursuant to recapture agreement				557,000
Interest Expense				1,280,000
Repayments				(134,624,000)
Change in fair value				1,037,000
Excess servicing spread recapture recognized				$ 614,000