Related Party Transactions - Mortgage Loan Servicing (Details) - USD ($)				3 Months Ended		9 Months Ended
	Oct. 01, 2025	Jan. 01, 2025	Sep. 12, 2016	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Summary of mortgage loan servicing fees earned
Servicing fees				$ 535,106,000	$ 462,037,000	$ 1,530,241,000	$ 1,326,917,000
Loan Servicing Agreement
Transactions with Affiliates
Base servicing fees per month for REO			$ 75
Base servicing fees per month for fixed-rate non-distressed loans subserviced	$ 7		7.5
Base servicing fees per month for adjustable rate non-distressed loans subserviced	$ 8		8.5
Supplemental fee per month for each distressed whole loan			25
Minimum | Loan Servicing Agreement
Transactions with Affiliates
Servicing fees amount per month for current loans			30
Servicing fees amount per month for severely delinquent loans		$ 18
Additional servicing fee amount per month for delinquent loans			10
Maximum | Loan Servicing Agreement
Transactions with Affiliates
Servicing fees amount per month for current loans			95
Servicing fees amount per month for severely delinquent loans		$ 80
Additional servicing fee amount per month for delinquent loans			$ 55
Related Party | PennyMac Mortgage Investment Trust
Summary of mortgage loan servicing fees earned
Servicing fees				21,012,000	22,240,000	64,386,000	62,766,000
Related Party | Loans acquired for sale at fair value | PennyMac Mortgage Investment Trust
Summary of mortgage loan servicing fees earned
Base and supplemental				19,032,000	19,243,000	57,386,000	57,621,000
Activity-based				1,980,000	2,997,000	7,000,000	5,145,000
Servicing fees				$ 21,012,000	$ 22,240,000	$ 64,386,000	$ 62,766,000