Mortgage Servicing Rights and Mortgage Servicing Liabilities - Servicing, Late, Ancillary and Other Fees Relating to MSRs (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Other fees:
Loan servicing fees	$ 387,934	$ 313,080	$ 1,082,462	$ 906,688
Mortgage servicing rights
Contractual servicing fees	328,049	270,336	925,865	774,483
Other fees:
Late charges	14,486	10,533	39,984	30,177
Other	2,708	2,952	7,664	11,487
Loan servicing fees	$ 345,243	$ 283,821	$ 973,513	$ 816,147

N/A

No definition available.

Name:	pfsi_LateFeesAndAncillaryFeesEarnedInExchangeForServicingFinancialAssetsAbstract
Namespace Prefix:	pfsi_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

All amounts that are due to the servicer of a financial asset, excluding contractually specified servicing fees and late fees.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-2

+ Details

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

- Definition

All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

+ References

+ Details

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

- Definition

Amount of contractually specified servicing fee, late fee, and ancillary fee recognized as income for servicing asset and servicing liability.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-2

+ Details

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

- Definition

All amounts that are due to the servicer of a financial asset as a result of the debt holder not meeting the monthly payment terms.

+ References

+ Details

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

- Details

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