Financing - Underlying Assets of Repurchase Agreements when Amount of Repurchase Agreements Exceeds 10 Percent of Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Assets Sold under Agreements to Repurchase [Line Items]
Assets pledged as collateral for repurchase agreements	$ 6,198,047	$ 7,850,175
Repurchase agreements	5,639,830	7,255,540
Available-for-sale securities, at fair value
Assets Sold under Agreements to Repurchase [Line Items]
Assets pledged as collateral for repurchase agreements	5,084,098	6,505,374
Mortgage servicing rights, at fair value
Assets Sold under Agreements to Repurchase [Line Items]
Assets pledged as collateral for repurchase agreements	923,087	958,947
Repurchase agreements	575,000	650,000
Mortgage servicing rights, at fair value \| Variable Funding Note
Assets Sold under Agreements to Repurchase [Line Items]
Repurchase agreements	575,000	650,000
Mortgage loans held-for-sale, at fair value
Assets Sold under Agreements to Repurchase [Line Items]
Assets pledged as collateral for repurchase agreements	7,806	3,746
Repurchase agreements	7,506	4,094
Restricted cash
Assets Sold under Agreements to Repurchase [Line Items]
Assets pledged as collateral for repurchase agreements	123,861	108,367
Due from counterparties
Assets Sold under Agreements to Repurchase [Line Items]
Assets pledged as collateral for repurchase agreements	5,984	206,514
Derivative assets, at fair value
Assets Sold under Agreements to Repurchase [Line Items]
Assets pledged as collateral for repurchase agreements	$ 53,211	$ 67,227