Fair Value - Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Financial assets:
Loans and investments, net	$ 14,791,426	$ 11,981,048
Loans held-for-sale, net	552,306	1,077,239
Securities held-to-maturity, net	157,818	140,484
Financial liabilities:
Debt Carrying Value	4,633,132	4,481,579
Collateralized loan obligations	7,971,996	5,892,810
Senior unsecured notes	1,283,527	1,280,545
Convertible senior unsecured notes, net	346,040	259,385
Junior subordinated notes	142,933	142,382
Level 1
Financial liabilities:
Senior unsecured notes	1,165,125
Level 2
Financial assets:
Loans held-for-sale, net	546,633
Financial liabilities:
Debt Carrying Value	511,513
Convertible senior unsecured notes, net	327,244
Level 3
Financial assets:
Loans and investments, net	14,993,875
Loans held-for-sale, net	7,411
Capitalized mortgage servicing rights, net	530,859
Securities held-to-maturity, net	150,027
Financial liabilities:
Debt Carrying Value	4,111,159
Collateralized loan obligations	7,800,210
Junior subordinated notes	103,402
Carrying Value
Financial assets:
Loans and investments, net	14,791,426	11,981,048
Loans held-for-sale, net	543,876	1,093,609
Capitalized mortgage servicing rights, net	403,886
Securities held-to-maturity, net	157,818	140,484
Financial liabilities:
Debt Carrying Value	4,633,132	4,481,579
Collateralized loan obligations	7,971,996	5,892,810
Senior unsecured notes	1,283,527	1,280,545
Convertible senior unsecured notes, net	346,040	259,385
Junior subordinated notes	142,933	142,382
Fair Value
Financial assets:
Loans and investments, net	14,993,875	12,181,194
Loans held-for-sale, net	554,044	1,117,085
Capitalized mortgage servicing rights, net	530,859
Securities held-to-maturity, net	150,027	149,911
Financial liabilities:
Debt Carrying Value	4,622,672	4,484,107
Collateralized loan obligations	7,800,210	5,914,453
Senior unsecured notes	1,165,125	1,301,708
Convertible senior unsecured notes, net	327,244	294,690
Junior subordinated notes	$ 103,402	$ 101,698

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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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