Fair Value of Financial Instruments Significant Unobservable Inputs Level 3 (Details) - Fair Value, Measurements, Recurring - Level 3	12 Months Ended
	Dec. 31, 2016
CMBS
Fair Value Inputs, Quantitative Information [Abstract]
Fair Value Inputs, Prepayment Rate	0.00%	[1]
Fair Value Inputs, Probability of Default	0.00%	[1]
Fair Value Inputs, Loss Severity	0.00%	[1]
Fair Value Inputs, Discount Rate	9.80%
RMBS
Fair Value Inputs, Quantitative Information [Abstract]
Fair Value Inputs, Prepayment Rate	10.00%
Fair Value Inputs, Probability of Default	1.00%
Fair Value Inputs, Loss Severity	20.00%
Fair Value Inputs, Discount Rate	6.30%

[1] As of December 31, 2016, there are too few loans collateralizing our non-Agency CMBS to reasonably apply average prepayment speed, average default rate, or average severity. The loans were individually evaluated for prepayment and default in projecting the cash flows. Based on that review, the loans are expected to pay as scheduled.