Commitments and Contingencies - Other (Details) - USD ($) $ in Thousands		3 Months Ended
Oct. 24, 2018	Mar. 31, 2021
Contingencies
Total commitments to purchase and fund mortgage loans		$ 17,700,000
Garfield Action \| Settled Litigation
Contingencies
Percent of shareholder approval for reorganization of the company (as a percent)	99.80%
Litigation settlement amount		$ 6,850

Amount to be expended to satisfy the terms of arrangements in which the entity has agreed to expend to purchase and fund mortgage loans.

No definition available.

+ Details

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Namespace Prefix:	pfsi_
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Balance Type:	credit
Period Type:	instant

- Definition

Represents the percent of shareholder approval for reorganization of the company.

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Details

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Namespace Prefix:
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- Details

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