Fair Value - Schedule of Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Financial assets:
Loans and investments, net	$ 11,835,381	$ 11,934,248
Loans held-for-sale, net	444,956	408,386
Securities held-to-maturity, net	155,469	156,087
Financial liabilities:
Credit and repurchase facilities	4,967,952	5,149,651
Securitized debt	3,931,468	3,468,258
Senior unsecured notes	2,030,947	2,029,078
Junior subordinated notes	145,707	145,497
Notes payable - real estate owned	253,189	222,965
Level 1
Financial assets:
Loans and investments, net	0
Loans held-for-sale, net	0
Capitalized mortgage servicing rights, net	0
Securities held-to-maturity, net	0
Financial liabilities:
Credit and repurchase facilities	0
Securitized debt	0
Senior unsecured notes	1,968,663
Junior subordinated notes	0
Notes payable - real estate owned	0
Level 2
Financial assets:
Loans and investments, net	0
Loans held-for-sale, net	451,131
Capitalized mortgage servicing rights, net	0
Securities held-to-maturity, net	0
Financial liabilities:
Credit and repurchase facilities	424,865
Securitized debt	0
Senior unsecured notes	0
Junior subordinated notes	0
Notes payable - real estate owned	0
Level 3
Financial assets:
Loans and investments, net	11,821,573
Loans held-for-sale, net	4,994
Capitalized mortgage servicing rights, net	465,856
Securities held-to-maturity, net	149,237
Financial liabilities:
Credit and repurchase facilities	4,536,445
Securitized debt	3,954,507
Senior unsecured notes	0
Junior subordinated notes	112,772
Notes payable - real estate owned	252,010
Carrying Value
Financial assets:
Loans and investments, net	11,835,381	11,934,248
Loans held-for-sale, net	443,218	409,081
Capitalized mortgage servicing rights, net	331,929
Securities held-to-maturity, net	155,469	156,087
Financial liabilities:
Credit and repurchase facilities	4,967,952	5,149,651
Securitized debt	3,931,468	3,468,258
Senior unsecured notes	2,030,947	2,029,078
Junior subordinated notes	145,707	145,497
Notes payable - real estate owned	253,189	222,965
Fair Value
Financial assets:
Loans and investments, net	11,821,573	11,964,280
Loans held-for-sale, net	456,125	421,398
Capitalized mortgage servicing rights, net	465,856
Securities held-to-maturity, net	149,237	150,147
Financial liabilities:
Credit and repurchase facilities	4,961,310	5,143,472
Securitized debt	3,954,507	3,487,773
Senior unsecured notes	1,968,663	2,009,938
Junior subordinated notes	112,772	111,992
Notes payable - real estate owned	$ 252,010	$ 221,893

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Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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