v3.20.4

Investment in Securities (Summary of Investment Income) (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2020 | Sep. 30, 2020 | Jun. 30, 2020 | Mar. 31, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net Amortization |  |  |  |  |  |  |  |  |  |  |  |  | $ (41,681) | $ (48,132) | $ (45,895) |
Interest Income | $ 39,067 | $ 43,075 | $ 39,281 | $ 52,108 | $ 45,353 | $ 39,985 | $ 38,547 | $ 36,016 | $ 35,694 | $ 35,300 | $ 31,941 | $ 28,092 | 173,531 | 159,901 | $ 131,027 | [1]
Agency RMBS |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Coupon Interest |  |  |  |  |  |  |  |  |  |  |  |  | 59,987 | 62,103 |  |
Net Amortization |  |  |  |  |  |  |  |  |  |  |  |  | (31,975) | (24,731) |  |
Interest Income |  |  |  |  |  |  |  |  |  |  |  |  | 28,012 | 37,372 |  |
Non-Agency RMBS and CMBS |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Coupon Interest |  |  |  |  |  |  |  |  |  |  |  |  | 15,257 | 13,855 |  |
Net Amortization |  |  |  |  |  |  |  |  |  |  |  |  | 5,775 | 2,782 |  |
Interest Income |  |  |  |  |  |  |  |  |  |  |  |  | 21,032 | 16,637 |  |
CLOs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Coupon Interest |  |  |  |  |  |  |  |  |  |  |  |  | 14,103 | 15,857 |  |
Net Amortization |  |  |  |  |  |  |  |  |  |  |  |  | 3,529 | (1,599) |  |
Interest Income |  |  |  |  |  |  |  |  |  |  |  |  | 17,632 | 14,258 |  |
Other Securities |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Coupon Interest |  |  |  |  |  |  |  |  |  |  |  |  | 11,545 | 7,157 |  |
Net Amortization |  |  |  |  |  |  |  |  |  |  |  |  | (4,986) | (2,468) |  |
Interest Income |  |  |  |  |  |  |  |  |  |  |  |  | 6,559 | 4,689 |  |
Securities Investment [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Securities, Available-for-sale [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Coupon Interest |  |  |  |  |  |  |  |  |  |  |  |  | 100,892 | 98,972 |  |
Net Amortization |  |  |  |  |  |  |  |  |  |  |  |  | (27,657) | (26,016) |  |
Interest Income |  |  |  |  |  |  |  |  |  |  |  |  | $ 73,235 | $ 72,956 |  |
[1] | Includes interest income and interest expense of a consolidated securitization trust of $6.0 million and $3.6 million, respectively, for the year ended December 31, 2018. See Note 6 for further details on the Company's consolidated securitization trust.

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