Pledged financial instruments not separately reported and assets separately reported on statement at fair value.

No definition available.

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Namespace Prefix:	pmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Pledged financial instruments not separately reported Pledged securities.

+ References

No definition available.

+ Details

Name:	pmt_Pledgedfinancialinstrumentsnotseparatelyreportedpledgedsecurities
Namespace Prefix:	pmt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Market value of assets sold under agreements to repurchase when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under repurchase agreements exceeds 10 percent of total assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(1)(i))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(1)(ii)(A)(i))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

+ Details

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

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

- Definition

Fair value portion of mortgage loans held-for-sale.

+ References

No definition available.

+ Details

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

- Details

Name:	us-gaap_FairValueByAssetClassAxis=pmt_MortgageLoansAcquiredForSaleAtFairValueMember
Namespace Prefix:
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- Details

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

- Details

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

- Details

Name:	srt_MortgageLoansOnRealEstateLoanTypeAxis=pmt_GovernmentSponsoredEntityEligibleMember
Namespace Prefix:
Data Type:	na
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- Details

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Namespace Prefix:
Data Type:	na
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- Details

Name:	srt_MortgageLoansOnRealEstateLoanTypeAxis=pmt_GovernmentGuaranteedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MortgageLoansOnRealEstateLoanTypeAxis=pmt_JumboLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MortgageLoansOnRealEstateLoanTypeAxis=us-gaap_HomeEquityLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	srt_MortgageLoansOnRealEstateLoanTypeAxis=pmt_RepresentationsAndWarrantiesMember
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