Derivative Financial Instruments - Offsetting of Derivative Assets - Derivative Assets, Financial Assets, and Collateral Held by Counterparty (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Total
Net amounts of assets presented in the balance sheet	$ 200,303	$ 113,076
Net amount	200,303	113,076
RJ O' Brien
Total
Net amounts of assets presented in the balance sheet	26,389	15,842
Net amount	26,389	15,842
JPMorgan Chase Bank, N.A.
Total
Net amounts of assets presented in the balance sheet	3,283	334
Net amount	3,283	334
Barclays Capital
Total
Net amounts of assets presented in the balance sheet	3,692
Net amount	3,692
Morgan Stanley Bank, N.A.
Total
Net amounts of assets presented in the balance sheet	11,456	15,260
Net amount	11,456	15,260
Bank of America, N.A.
Total
Net amounts of assets presented in the balance sheet		8,221
Net amount		8,221
Ellington
Total
Net amounts of assets presented in the balance sheet	3,981
Net amount	3,981
Citibank, N.A.
Total
Net amounts of assets presented in the balance sheet	3,822	657
Net amount	3,822	657
Bank of Montreal
Total
Net amounts of assets presented in the balance sheet	2,571	3,781
Net amount	2,571	3,781
Mizuho Bank, Ltd.
Total
Net amounts of assets presented in the balance sheet	2,584	1,683
Net amount	2,584	1,683
Others
Total
Net amounts of assets presented in the balance sheet	8,509	5,740
Net amount	8,509	5,740
Athene Annuity & Life Assurance Company
Total
Net amounts of assets presented in the balance sheet		2,352
Net amount		2,352
BNP Paribas
Total
Net amounts of assets presented in the balance sheet	1,603	2,260
Net amount	1,603	2,260
PennyMac Mortgage Investment Trust
Total
Net amounts of assets presented in the balance sheet	1,779
Net amount	1,779
Interest rate lock commitments
Total
Net amounts of assets presented in the balance sheet	132,413	56,946
Net amount	$ 132,413	$ 56,946