Fair Value, Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Financial assets:
Loans and investments, net	$ 3,097,689	$ 2,579,127
Securities held-to-maturity, net	50,520	27,837
Financial liabilities:
Credit and repurchase facilities, Carrying value	1,169,586	528,573
Collateralized loan obligations	1,592,089	1,418,422
Debt fund	68,099	68,084
Senior unsecured notes	122,358	95,280
Convertible senior unsecured notes, net	263,653	231,287
Junior subordinated notes	140,084	139,590
Level 1
Financial liabilities:
Senior unsecured notes	124,375
Level 2
Financial assets:
Loans held-for-sale, net	499,239
Financial liabilities:
Credit and repurchase facilities, Carrying value	492,603
Convertible senior unsecured notes, net	289,560
Level 3
Financial assets:
Loans and investments, net	3,154,139
Loans held-for-sale, net	8,459
Capitalized mortgage servicing rights, net	312,316
Securities held-to-maturity, net	52,312
Financial liabilities:
Credit and repurchase facilities, Carrying value	677,632
Collateralized loan obligations	1,616,293
Debt fund	70,135
Junior subordinated notes	95,458
Carrying Value
Financial assets:
Loans and investments, net	3,097,689	2,579,127
Loans held-for-sale, net	500,281	297,443
Capitalized mortgage servicing rights, net	259,401
Securities held-to-maturity, net	50,520	27,837
Financial liabilities:
Credit and repurchase facilities, Carrying value	1,169,586	528,573
Collateralized loan obligations	1,592,089	1,418,422
Debt fund	68,099	68,084
Senior unsecured notes	122,358	95,280
Convertible senior unsecured notes, net	263,653	231,287
Junior subordinated notes	140,084	139,590
Fair Value
Financial assets:
Loans and investments, net	3,154,139	2,652,520
Loans held-for-sale, net	507,698	302,883
Capitalized mortgage servicing rights, net	312,316
Securities held-to-maturity, net	52,312	28,439
Financial liabilities:
Credit and repurchase facilities, Carrying value	1,170,235	529,992
Collateralized loan obligations	1,616,293	1,436,871
Debt fund	70,135	70,000
Senior unsecured notes	124,375	99,582
Convertible senior unsecured notes, net	289,560	254,335
Junior subordinated notes	$ 95,458	$ 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 of investment in debt security measured at amortized cost (held-to-maturity).

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