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

Revenues for operating and managing another entity's business during the reporting period which is based on meeting certain operating or revenue metrics (for example: occupancy or vacancy rates, profitability or expense targets), or otherwise meant to incentivize the operator other than by guaranteed or minimum compensation.

No definition available.

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

Revenues, comprised of base and incentive revenue derived from the management of joint ventures, managing third-party properties, or another entity's operations.

No definition available.

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

Not available.

No definition available.

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

Related Party Transaction High Watermark for Performance Incentive Fee Computation

No definition available.

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

Related Party Transaction, Percentage of Affiliate Equity Considered to Calculate Base Management Fee

No definition available.

Name:	pfsi_RelatedPartyTransactionPercentageOfAffiliateEquityConsideredToCalculateBaseManagementFee
Namespace Prefix:	pfsi_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Related Party Transaction Percentage of Change in Net Income (Loss) for Performance Incentive Fee Computation

No definition available.

Name:	pfsi_RelatedPartyTransactionPercentageOfChangeInNetIncomeLossForPerformanceIncentiveFeeComputation
Namespace Prefix:	pfsi_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Related Party Transaction, Percentage of Performance Incentive Fee Payable by Issuance of Common Shares

No definition available.

Name:	pfsi_RelatedPartyTransactionPercentageOfPerformanceIncentiveFeePayableByIssuanceOfCommonShares
Namespace Prefix:	pfsi_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Related Party Transaction, Percentage of Return on Affiliate Equity Considered to Calculate Performance Incentive Fee

No definition available.

Name:	pfsi_RelatedPartyTransactionPercentageOfReturnOnAffiliateEquityConsideredToCalculatePerformanceIncentiveFee
Namespace Prefix:	pfsi_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Related Party Transaction, Specified Percentage Applied on Excess of Core Earnings on Rolling Quarter Basis before Incentive Fee over Hurdle Rate for Performance Incentive Fee Computation

No definition available.

Name:	pfsi_RelatedPartyTransactionSpecifiedPercentageAppliedOnExcessOfCoreEarningsOnRollingQuarterBasisBeforeIncentiveFeeOverHurdleRateForPerformanceIncentiveFeeComputation
Namespace Prefix:	pfsi_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

Related Party Transaction, Threshold Shareholders Equity Considered to Calculate Base Management Fee

No definition available.

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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=pfsi_PennyMacMortgageInvestmentTrustMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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

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

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

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

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