Net Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Interest income:
Interest income	$ 221,929	$ 200,811	$ 411,800	$ 357,237
Interest expense:
Interest expense	239,577	207,871	447,659	373,640
Net interest expense	(17,648)	(7,060)	(35,859)	(16,403)
Nonrelated Party
Interest income:
Cash and short-term investments	10,919	13,172	20,926	27,754
Principal-only stripped mortgage-backed securities	6,948	9,074	18,543	9,344
Loans held for sale	105,725	86,283	193,119	151,704
Placement fees relating to custodial funds	97,975	92,230	177,770	168,363
Other	362	52	1,442	72
Interest expense:
Assets sold under agreements to repurchase	112,685	106,587	206,914	177,022
Mortgage loan participation purchase and sale agreements	4,168	4,109	7,972	8,186
Notes payable secured by mortgage servicing assets	35,743	41,932	72,321	85,938
Unsecured senior notes	70,157	43,968	130,294	82,800
Interest shortfall on repayments of mortgage loans serviced for Agency securitizations	14,058	7,902	23,832	14,023
Interest on mortgage loan impound deposits	2,263	2,962	4,844	4,949
Other	503	411	1,482	722
Interest expense	239,577	207,871	447,659	373,640
Loan Repo Facility
Interest expense:
Assets sold under agreements to repurchase	$ 112,685	$ 106,587	$ 206,914	$ 177,022