Fair Value - Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Financial assets:
Loans and investments, net	$ 11,215,625	$ 11,033,997
Loans held-for-sale, net	315,700	438,233
Securities held-to-maturity, net	158,658	157,154
Financial liabilities:
Credit and repurchase facilities	4,780,753	3,559,490
Securitized debt	3,286,395	4,622,489
Senior unsecured notes	1,237,160	1,236,147
Convertible senior unsecured notes	286,555	285,853
Junior subordinated notes	144,890	144,686
Mortgage notes payable — real estate owned	123,851	74,897
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	1,136,669
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	320,967
Capitalized mortgage servicing rights, net	0
Securities held-to-maturity, net	0
Financial liabilities:
Credit and repurchase facilities	279,404
Securitized debt	0
Senior unsecured notes	0
Convertible senior unsecured notes	287,213
Junior subordinated notes	0
Mortgage notes payable — real estate owned	0
Level 3
Financial assets:
Loans and investments, net	11,248,443
Loans held-for-sale, net	3,554
Capitalized mortgage servicing rights, net	492,930
Securities held-to-maturity, net	149,283
Financial liabilities:
Credit and repurchase facilities	4,516,963
Securitized debt	3,285,150
Senior unsecured notes	0
Convertible senior unsecured notes	0
Junior subordinated notes	109,821
Mortgage notes payable — real estate owned	122,975
Carrying Value
Financial assets:
Loans and investments, net	11,215,625	11,033,997
Loans held-for-sale, net	314,635	435,759
Capitalized mortgage servicing rights, net	357,220
Securities held-to-maturity, net	158,658	157,154
Financial liabilities:
Credit and repurchase facilities	4,780,753	3,559,490
Securitized debt	3,286,395	4,622,489
Senior unsecured notes	1,237,160	1,236,147
Convertible senior unsecured notes	286,555	285,853
Junior subordinated notes	144,890	144,686
Mortgage notes payable — real estate owned	123,851	74,897
Fair Value
Financial assets:
Loans and investments, net	11,248,443	11,122,205
Loans held-for-sale, net	324,521	449,339
Capitalized mortgage servicing rights, net	492,930
Securities held-to-maturity, net	149,283	144,508
Financial liabilities:
Credit and repurchase facilities	4,796,367	3,592,120
Securitized debt	3,285,150	4,616,409
Senior unsecured notes	1,136,669	1,160,154
Convertible senior unsecured notes	287,213	287,500
Junior subordinated notes	109,821	109,099
Mortgage notes payable — real estate owned	$ 122,975	$ 74,495

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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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