Fair Value - Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Financial assets:
Loans and investments, net	$ 11,292,647	$ 12,377,806
Loans held-for-sale, net	326,910	552,325
Securities held-to-maturity, net	156,027	155,279
Financial liabilities:
Credit and repurchase facilities	3,257,719	3,237,827
Securitized debt	5,315,079	6,935,010
Senior unsecured notes	1,246,908	1,333,968
Convertible senior unsecured notes	285,170	283,118
Junior subordinated notes	144,480	143,896
Mortgage notes payable — real estate owned	35,350	44,339
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	1,161,256
Convertible senior unsecured notes	0
Junior subordinated notes	0
Mortgage notes payable — real estate owned	0
Level 2
Financial assets:
Loans and investments, net	0
Loans held-for-sale, net	330,997
Capitalized mortgage servicing rights, net	0
Securities held-to-maturity, net	0
Financial liabilities:
Credit and repurchase facilities	319,419
Securitized debt	0
Senior unsecured notes	0
Convertible senior unsecured notes	292,712
Junior subordinated notes	0
Mortgage notes payable — real estate owned	0
Level 3
Financial assets:
Loans and investments, net	11,236,801
Loans held-for-sale, net	3,887
Capitalized mortgage servicing rights, net	499,630
Securities held-to-maturity, net	145,000
Financial liabilities:
Credit and repurchase facilities	2,928,081
Securitized debt	5,281,765
Senior unsecured notes	0
Convertible senior unsecured notes	0
Junior subordinated notes	107,761
Mortgage notes payable — real estate owned	35,132
Carrying Value
Financial assets:
Loans and investments, net	11,292,647	12,377,806
Loans held-for-sale, net	326,141	551,707
Capitalized mortgage servicing rights, net	376,403
Securities held-to-maturity, net	156,027	155,279
Financial liabilities:
Credit and repurchase facilities	3,257,719	3,237,827
Securitized debt	5,315,079	6,935,010
Senior unsecured notes	1,246,908	1,333,968
Convertible senior unsecured notes	285,170	283,118
Junior subordinated notes	144,480	143,896
Mortgage notes payable — real estate owned	35,350	44,339
Fair Value
Financial assets:
Loans and investments, net	11,236,801	12,452,563
Loans held-for-sale, net	334,884	566,451
Capitalized mortgage servicing rights, net	499,630
Securities held-to-maturity, net	145,000	129,390
Financial liabilities:
Credit and repurchase facilities	3,247,500	3,228,324
Securitized debt	5,281,765	6,864,557
Senior unsecured notes	1,161,256	1,214,331
Convertible senior unsecured notes	292,712	301,156
Junior subordinated notes	107,761	106,444
Mortgage notes payable — real estate owned	$ 35,132	$ 44,103

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Carrying value as of the balance sheet date, of securities sold under agreements to repurchase and the carrying value, as of the balance sheet date, of the outstanding borrowings under warehouse and revolving lines of credit.

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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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Including the current and noncurrent portions, the carrying value of junior subordinated long-term debt owed to unconsolidated subsidiary trusts as of the balance sheet date. Such debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets and was initially scheduled to be repaid after one year or beyond the normal operating cycle if longer.

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Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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