Mortgage-Backed Securities and other securities - Financing receivables (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Other than temporary impairment	$ 0	$ 1,232
Components of interest income
Net (Premium Amortization/Amortization Basis) Discount Amortization	(1,837)	(357)
Interest Income	54,846	52,033
Agency CMBS
Components of interest income
Coupon Interest	10,923	10,989
Net (Premium Amortization/Amortization Basis) Discount Amortization	(588)	(56)
Interest Income	10,335	10,933
Subtotal Agency
Debt Securities, Available-for-sale [Line Items]
Other than temporary impairment		25
Components of interest income
Coupon Interest	2,756	871
Net (Premium Amortization/Amortization Basis) Discount Amortization	(842)	(655)
Interest Income	1,914	216
Non-Agency RMBS
Debt Securities, Available-for-sale [Line Items]
Other than temporary impairment		966
Components of interest income
Coupon Interest	4,797	3,111
Net (Premium Amortization/Amortization Basis) Discount Amortization	968	924
Interest Income	5,765	4,035
Non-Agency CMBS
Debt Securities, Available-for-sale [Line Items]
Other than temporary impairment		241
Components of interest income
Coupon Interest	1,151	1,207
Net (Premium Amortization/Amortization Basis) Discount Amortization	(641)	(477)
Interest Income	510	730
Other securities
Components of interest income
Coupon Interest	2,805	2,889
Net (Premium Amortization/Amortization Basis) Discount Amortization	(1,464)	(1,591)
Interest Income	1,341	1,298
Total
Components of interest income
Coupon Interest	22,432	19,067
Net (Premium Amortization/Amortization Basis) Discount Amortization	(2,567)	(1,855)
Interest Income	$ 19,865	$ 17,212

The sum of the periodic adjustments of the differences between securities' face values and purchase prices that are charged against earnings. This is called accretion if the security was purchased at a discount and amortization if it was purchased at premium. As a noncash item, this element is an adjustment to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of operating interest income, including, but not limited to, amortization and accretion of premiums and discounts on securities.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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