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Schedule of Mortgage-Backed Securities by Weighted Average Life (Details) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 1,050,521 | $ 1,401,778
Non-Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | 7,520 | 8,851
Amortized Cost | $ 6,620 | $ 6,924
Weighted Average Coupon Rate, Percent | 3.26% | 3.73%
Less than three years [Member] | Non-Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 1,840 | $ 4,000
Amortized Cost | $ 1,779 | $ 3,823
Weighted Average Coupon Rate, Percent | 5.01% | 5.35%
Greater than three years and less than seven years [Member] | Non-Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 1,636 | $ 784
Amortized Cost | $ 351 | $ 307
Weighted Average Coupon Rate, Percent | 2.19% | 3.88%
Greater than seven years and less than eleven years [Member] | Non-Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 2,226 | $ 4,067
Amortized Cost | $ 2,656 | $ 2,794
Weighted Average Coupon Rate, Percent | 1.58% | 2.29%
Greater than eleven years [Member] | Non-Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 1,818 | $ 0
Amortized Cost | $ 1,834 | $ 0
Weighted Average Coupon Rate, Percent | 5.78% | 0.00%
Fixed Rate [Member] | Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 1,027,372 | $ 1,374,683
Amortized Cost | $ 994,067 | $ 1,351,210
Weighted Average Coupon Rate, Percent | 4.08% | 4.10%
Fixed Rate [Member] | Less than three years [Member] | Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 140,016 | $ 53,620
Amortized Cost | $ 136,852 | $ 52,683
Weighted Average Coupon Rate, Percent | 4.33% | 4.72%
Fixed Rate [Member] | Greater than three years and less than seven years [Member] | Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 842,456 | $ 793,820
Amortized Cost | $ 812,785 | $ 778,950
Weighted Average Coupon Rate, Percent | 4.03% | 4.18%
Fixed Rate [Member] | Greater than seven years and less than eleven years [Member] | Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 44,900 | $ 496,334
Amortized Cost | $ 44,430 | $ 488,956
Weighted Average Coupon Rate, Percent | 4.06% | 3.92%
Fixed Rate [Member] | Greater than eleven years [Member] | Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 0 | $ 30,909
Amortized Cost | $ 0 | $ 30,621
Weighted Average Coupon Rate, Percent | 0.00% | 3.97%
Interest-Only [Member] | Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 15,629 | $ 18,244
Amortized Cost | $ 17,266 | $ 17,795
Weighted Average Coupon Rate, Percent | 3.25% | 3.22%
Interest-Only [Member] | Less than three years [Member] | Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 5,309 | $ 3,695
Amortized Cost | $ 5,855 | $ 3,407
Weighted Average Coupon Rate, Percent | 4.60% | 4.53%
Interest-Only [Member] | Greater than three years and less than seven years [Member] | Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 10,190 | $ 14,446
Amortized Cost | $ 11,308 | $ 14,283
Weighted Average Coupon Rate, Percent | 2.68% | 2.93%
Interest-Only [Member] | Greater than seven years and less than eleven years [Member] | Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 130 | $ 103
Amortized Cost | $ 103 | $ 105
Weighted Average Coupon Rate, Percent | 0.34% | 0.33%
Interest-Only [Member] | Greater than eleven years [Member] | Agency RMBS [Member] |  |
Mortgage-Backed Securities [Line Items] |  |
Mortgage-backed securities, at fair value | $ 0 | $ 0
Amortized Cost | $ 0 | $ 0
Weighted Average Coupon Rate, Percent | 0.00% | 0.00%

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- Definition The fair value as of the balance sheet date of firm holdings in mortgages, mortgage backed securities (investment instruments that represent ownership of an undivided interest in a group of mortgages, where principal and interest from the individual mortgages are used to pay investors' principal and interest on the mortgage backed security) and asset-backed securities that are primarily paid from the cash flows of a discrete pool of receivables or other financial assets (such as credit-card receivables), either fixed or revolving, that by their terms convert into cash within a finite time period. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969 + Details
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