Investments (Details) |
1 Months Ended | 3 Months Ended | 12 Months Ended | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Oct. 31, 2016
USD ($)
|
Mar. 31, 2019
USD ($)
loan
|
Dec. 31, 2018
USD ($)
loan
|
Mar. 31, 2018
USD ($)
|
Dec. 31, 2018
USD ($)
|
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Available-for-sale Securities, Amortized Cost Basis [Abstract] | |||||||||||
Investment in debt securities - Basis | $ 152,261,000 | $ 147,386,000 | $ 147,386,000 | ||||||||
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract] | |||||||||||
Investment in debt securities - Gross unrealized gains | 410,000 | 250,000 | 250,000 | ||||||||
Available-for-sale Securities [Abstract] | |||||||||||
Investment in debt securities | 152,083,000 | 146,811,000 | 146,811,000 | ||||||||
Investment in debt securities - Gross unrealized loss | (588,000) | $ (825,000) | (825,000) | ||||||||
Proceeds from Sale of Available-for-sale Securities, Debt | 39,635,000 | $ 0 | |||||||||
Gain (Loss) on Sale of Securities, Net | $ 8,000 | ||||||||||
Number of loans | loan | 7,018 | 7,111 | |||||||||
Secured Debt | [1],[2],[3] | $ 593,121,000 | $ 610,199,000 | 610,199,000 | |||||||
Purchase of debt securities | 64,014,000 | $ 0 | |||||||||
Investments in beneficial interests | 30,809,000 | 22,086,000 | 22,086,000 | ||||||||
Oileus Residential Loan Trust | |||||||||||
Available-for-sale Securities [Abstract] | |||||||||||
Purchase of debt securities | $ 6,300,000 | ||||||||||
Available-for-sale Securities, Gross Realized Gains | 200,000 | ||||||||||
Senior Notes | |||||||||||
Available-for-sale Securities [Abstract] | |||||||||||
Investment in debt securities | 50,000,000 | 144,100,000 | 144,100,000 | ||||||||
Subordinated Debt | |||||||||||
Available-for-sale Securities [Abstract] | |||||||||||
Investment in debt securities | 4,600,000 | 9,400,000 | 9,400,000 | ||||||||
Accumulated Net Investment Gain (Loss) Attributable to Noncontrolling Interest | |||||||||||
Available-for-sale Securities, Amortized Cost Basis [Abstract] | |||||||||||
Investment in beneficial interests - Basis | 183,070,000 | 169,472,000 | 169,472,000 | ||||||||
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract] | |||||||||||
Investment in beneficial interests - Gross unrealized gains | 250,000 | 250,000 | |||||||||
Investment in beneficial interests - Gross unrealized loss | (825,000) | (825,000) | |||||||||
Available-for-sale Securities [Abstract] | |||||||||||
Investment in beneficial interests | 182,892,000 | 168,897,000 | 168,897,000 | ||||||||
Beneficial interests | |||||||||||
Available-for-sale Securities, Amortized Cost Basis [Abstract] | |||||||||||
Investment in beneficial interests - Basis | 30,809,000 | 22,086,000 | 22,086,000 | ||||||||
Available-for-sale Securities, Gross Unrealized Gain (Loss) [Abstract] | |||||||||||
Investment in beneficial interests - Gross unrealized gains | 0 | 0 | 0 | ||||||||
Investment in beneficial interests - Gross unrealized loss | 0 | 0 | 0 | ||||||||
Available-for-sale Securities [Abstract] | |||||||||||
Investment in beneficial interests | 30,809,000 | 22,086,000 | 22,086,000 | ||||||||
Beneficial interests | |||||||||||
Available-for-sale Securities [Abstract] | |||||||||||
Investments in beneficial interests | $ 9,500,000 | $ 21,800,000 | $ 21,800,000 | ||||||||
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