Concentration of Risk (Details) - PennyMac Mortgage Investment Trust - Customer Concentration Risk	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Net Revenue
Concentration of Risk
Percentage of total	14.00%	6.00%
Loan Production
Concentration of Risk
Percentage of total	84.00%	55.00%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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-URI https://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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