Concentration of Risk (Details) - PennyMac Mortgage Investment Trust - Customer Concentration Risk	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Net Revenue
Concentration of Risk
Percentage of total net revenue	6.00%	9.00%
Loan Production
Concentration of Risk
Percentage of total net revenue	55.00%	54.00%

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
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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