Residential Whole Loans (Fair Value Components of Net Income) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Receivables [Abstract]
Coupon payments and other income received	$ 20,176	$ 17,634	$ 61,060	$ 52,034
Net unrealized gains	13,185	8,442	33,312	26,788
Net gain on payoff/liquidation of loans	2,026	3,251	6,906	10,203
Net gain on transfers to REO	4,788	5,615	15,637	16,858
Total	$ 40,175	$ 34,942	$ 116,915	$ 105,883

Mortgage Loans on Real Estate, Gain (Loss) on Loans at Fair Value

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Residential Whole Loans, Fair Value, Net Income (Loss), Coupon Payments Received

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Residential Whole Loans, Fair Value, Net Income (Loss), Gain (Loss) on Pay-off or Liquidation of Loans

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Residential Whole Loans, Fair Value, Net Income (Loss), Gain (Loss) on Transfers to REO

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Residential Whole Loans, Fair Value, Net Income (Loss), Unrealized Gains (Losses), Net

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