Fair Value, Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Financial assets:
Loans and investments, net	$ 2,702,097	$ 2,579,127
Securities held-to-maturity, net	36,764	27,837
Financial liabilities:
Credit and repurchase facilities, Carrying value	626,063	528,573
Collateralized loan obligations	1,419,838	1,418,422
Debt fund	68,176	68,084
Senior unsecured notes	196,090	95,280
Convertible senior unsecured notes, net	232,577	231,287
Junior subordinated notes	139,760	139,590
Level 1
Financial liabilities:
Senior unsecured notes	98,995
Level 2
Financial assets:
Loans held-for-sale, net	286,953
Financial liabilities:
Credit and repurchase facilities, Carrying value	281,338
Senior unsecured notes	100,000
Convertible senior unsecured notes, net	254,727
Level 3
Financial assets:
Loans and investments, net	2,774,333
Loans held-for-sale, net	5,200
Capitalized mortgage servicing rights, net	299,392
Securities held-to-maturity, net	37,273
Financial liabilities:
Credit and repurchase facilities, Carrying value	347,172
Collateralized loan obligations	1,438,567
Debt fund	70,139
Junior subordinated notes	94,638
Carrying Value
Financial assets:
Loans and investments, net	2,702,097	2,579,127
Loans held-for-sale, net	286,325	297,443
Capitalized mortgage servicing rights, net	255,732
Securities held-to-maturity, net	36,764	27,837
Financial liabilities:
Credit and repurchase facilities, Carrying value	626,063	528,573
Collateralized loan obligations	1,419,838	1,418,422
Debt fund	68,176	68,084
Senior unsecured notes	196,090	95,280
Convertible senior unsecured notes, net	232,577	231,287
Junior subordinated notes	139,760	139,590
Fair Value
Financial assets:
Loans and investments, net	2,774,333	2,652,520
Loans held-for-sale, net	292,153	302,883
Capitalized mortgage servicing rights, net	299,392
Securities held-to-maturity, net	37,273	28,439
Financial liabilities:
Credit and repurchase facilities, Carrying value	628,510	529,992
Collateralized loan obligations	1,438,567	1,436,871
Debt fund	70,139	70,000
Senior unsecured notes	198,995	99,582
Convertible senior unsecured notes, net	254,727	254,335
Junior subordinated notes	$ 94,638	$ 94,215

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of commercial real estate debt fund (with maturities initially due after one year or beyond the operating cycle, if longer). The Debt fund is secured by a portfolio of loan obligations, which includes first mortgage bridge loans, senior participations interests in first mortgage bridge loans, subordinate participation interest in first mortgage bridge loans and participation interests in mezzanine loans. The Debt Fund allows, for a period of three years, principal proceeds from portfolio assets to be reinvested in qualifying replacement assets, subject to certain conditions.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Amount, after allowance for bad debt, of mortgage loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities.

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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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