Fair Value, Carrying Value and Estimated Fair Value (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Financial assets:
Loans and investments, net - Principal/Notional Amount	$ 7,385,929	$ 5,475,082
Loans and investments, net	7,213,915	5,285,868
Loans held-for-sale, net - Principal/Notional Amount	448,940	968,595
Loans held-for-sale, net	448,940	968,595
Securities, held-to-maturity, net - Principal/Notional Amount	171,001	140,124
Securities held-to-maturity, net	114,696	95,524
Derivative financial instruments - Principal/Notional Amount	308,421	865,975
Financial liabilities:
Credit and repurchase facilities, Principal/Notional Amount	2,021,412	2,238,722
Credit and repurchase facilities, Carrying value	2,015,188	2,234,883
Collateralized loan obligations	3,484,088	2,517,309
Senior unsecured notes	836,074	662,843
Convertible senior unsecured notes, net	270,917	267,973
Junior subordinated notes	142,013	141,656
Derivative financial instruments - Principal/Notional Amount	$ 36,198	319,142
Minimum
Financial liabilities:
Period of loans held for sale sold	60 days
Maximum
Financial liabilities:
Period of loans held for sale sold	180 days
Carrying Value
Financial assets:
Loans and investments, net	$ 7,213,915	5,285,868
Loans held-for-sale, net	457,647	986,919
Capitalized mortgage servicing rights, net	418,653	379,974
Securities held-to-maturity, net	114,696	95,524
Derivative financial instruments	2,387	3,892
Financial liabilities:
Credit and repurchase facilities, Carrying value	2,015,188	2,234,883
Collateralized loan obligations	3,484,088
Senior unsecured notes	836,074
Convertible senior unsecured notes, net	270,917
Junior subordinated notes	142,013
Derivative financial instruments	393	1,221
Fair Value
Financial assets:
Loans and investments, net	7,421,181	5,428,141
Loans held-for-sale, net	469,195	1,007,294
Capitalized mortgage servicing rights, net	471,275	415,495
Securities held-to-maturity, net	125,003	94,128
Derivative financial instruments	2,387	3,892
Financial liabilities:
Credit and repurchase facilities, Carrying value	2,016,291	2,235,668
Collateralized loan obligations	3,506,460
Senior unsecured notes	853,814
Convertible senior unsecured notes, net	304,689
Junior subordinated notes	100,650
Derivative financial instruments	393	1,221
CLOs
Financial liabilities:
Collateralized loan obligations	3,484,088	2,517,309
Debt instrument - Principal/Notional Amount	3,506,080	2,532,343
Collateralized Debt Obligations \| Carrying Value
Financial liabilities:
Collateralized loan obligations	3,484,088	2,517,309
Collateralized Debt Obligations \| Fair Value
Financial liabilities:
Collateralized loan obligations	3,506,460	2,495,195
Senior Unsecured Notes
Financial liabilities:
Debt instrument - Principal/Notional Amount	845,750	670,750
Senior Unsecured Notes \| Carrying Value
Financial liabilities:
Debt instrument - Principal/Notional Amount	836,074	662,843
Senior Unsecured Notes \| Fair Value
Financial liabilities:
Debt instrument - Principal/Notional Amount	853,814	670,117
Convertible Senior Unsecured Notes
Financial liabilities:
Debt instrument - Principal/Notional Amount	278,300	278,300
Convertible Senior Unsecured Notes \| Carrying Value
Financial liabilities:
Debt instrument - Principal/Notional Amount	270,917	267,973
Convertible Senior Unsecured Notes \| Fair Value
Financial liabilities:
Debt instrument - Principal/Notional Amount	304,689	280,636
Junior subordinated notes
Financial liabilities:
Junior subordinated notes	142,000	141,700
Debt instrument - Principal/Notional Amount	154,336	154,336
Junior subordinated notes \| Carrying Value
Financial liabilities:
Debt instrument - Principal/Notional Amount	142,013	141,656
Junior subordinated notes \| Fair Value
Financial liabilities:
Debt instrument - Principal/Notional Amount	$ 100,650	$ 99,594

Fair value of capitalized mortgage servicing rights.

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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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