Related Party Transactions - Exchanged Private National Mortgage Acceptance Company, LLC Unitholders (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Dec. 31, 2023
Transactions with Affiliates
Amount of tax benefits under the tax sharing agreement (as a percent)			85.00%
Repricing of payable to exchanged Private National Mortgage Acceptance Company, LLC unitholders under tax receivable agreement			$ (1,092)
Payable to exchanged PNMAC unitholders under tax receivable agreement	$ 24,800	$ 25,900	24,800	$ 25,900	$ 25,900	$ 25,900
Interest income	248,753	225,470	660,553	582,707
Related Party | Private National Mortgage Acceptance Company
Transactions with Affiliates
Payment of tax liability under the tax receivable agreement to Private National Mortgage Acceptance Company, LLC unitholders	0	$ 0	$ 0	$ 0
Reduction in liability related to change in tax rate applicable to deferred income tax liability	$ 1,100