Reverse Mortgage Loan Portfolio - Schedule of Composition and Remaining UPBs of Reverse Mortgage Loan Portfolio (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans held for investment, subject to HMBS related obligations	$ 23,375,525	$ 17,983,144
Total loans held for investment, subject to nonrecourse debt	10,546,878	9,567,732
Loans held for investment	487,528	790,342
Loans held for sale	144,955	34,515
Reverse mortgage loans
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans held for investment, subject to HMBS related obligations	23,375,525	17,983,144
Total loans held for investment, subject to nonrecourse debt	10,546,878	9,567,732
Loans held for investment	481,732	783,323
Loans held for sale	142,633	32,761
Total owned loan portfolio	34,546,768	28,366,960
Total serviced loan portfolio	35,103,134	29,008,074
Non-agency reverse mortgages
Fair Value, Option, Quantitative Disclosures [Line Items]
Total loans held for investment, subject to nonrecourse debt	9,840,125	8,887,778
Loans held for investment	216,079	614,515
Performing HECM buyouts
Fair Value, Option, Quantitative Disclosures [Line Items]
Total loans held for investment, subject to nonrecourse debt	260,878	251,051
Nonperforming HECM buyouts
Fair Value, Option, Quantitative Disclosures [Line Items]
Total loans held for investment, subject to nonrecourse debt	445,875	428,903
HECM loans not securitized
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans held for investment	187,087	103,825
Unpoolable HECM loans
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans held for investment	$ 78,566	64,983
Maximum claim amount ("MCA") (in percent)	98.00%
Loans reclassified as government guaranteed receivable
Fair Value, Option, Quantitative Disclosures [Line Items]
Total serviced loan portfolio	$ 44,827	50,922
Loans serviced for others
Fair Value, Option, Quantitative Disclosures [Line Items]
Total serviced loan portfolio	511,539	590,192
Pledged As Collateral, Financing Lines Of Credit
Fair Value, Option, Quantitative Disclosures [Line Items]
Loans held for sale	$ 508,400	$ 753,200

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