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Stockholders' Equity (Details) $ / shares in Units, $ in Thousands |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 Months Ended | 12 Months Ended | 172 Months Ended |  |  |  |
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Nov. 15, 2019 $ / shares | Sep. 12, 2019 $ / shares | Aug. 09, 2019 $ / shares | Jun. 12, 2019 $ / shares | May 20, 2019 $ / shares | Mar. 06, 2019 $ / shares | Feb. 15, 2019 $ / shares | Dec. 12, 2018 $ / shares | Nov. 26, 2018 $ / shares | Sep. 13, 2018 $ / shares | Aug. 20, 2018 $ / shares | Jun. 07, 2018 $ / shares | May 17, 2018 $ / shares | Mar. 07, 2018 $ / shares | Feb. 20, 2018 $ / shares | Dec. 13, 2017 $ / shares | Nov. 17, 2017 $ / shares | Sep. 14, 2017 $ / shares | Aug. 10, 2017 $ / shares | Jun. 12, 2017 $ / shares | May 16, 2017 $ / shares | Mar. 08, 2017 $ / shares | Feb. 17, 2017 $ / shares | Apr. 15, 2013 $ / shares shares | Dec. 31, 2019 USD ($) $ / shares shares | Dec. 31, 2019 USD ($) quarter director $ / shares shares | Dec. 31, 2018 USD ($) $ / shares shares | Dec. 31, 2017 USD ($) $ / shares shares | Dec. 31, 2017 USD ($) $ / shares shares | Aug. 16, 2019 USD ($) | Dec. 31, 2013 shares | Aug. 08, 2013 shares | Aug. 31, 2005 shares
Dividends on Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, shares issued (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8,000,000 | 8,000,000 | 8,000,000 |  |  |  |  |  |
Preferred stock, dividend rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7.50% |  | 7.50% | 7.50% |  |  |  |  |  |
Preferred stock, par value (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.01 | $ 0.01 | $ 0.01 |  |  |  |  |  |
Maximum quarters without dividends to get voting rights, in quarters | quarter |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6 |  |  |  |  |  |  |
Minimum percentage of preferred shareholders required for approval |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 66.67% |  |  |  |  |  |  |
Dividends on Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, cash dividends declared (in dollars per share) | $ / shares |  |  | $ 0.20 |  | $ 0.20 |  | $ 0.20 |  | $ 0.20 |  | $ 0.20 |  | $ 0.20 |  | $ 0.20 |  | $ 0.20 |  | $ 0.20 |  | $ 0.20 |  | $ 0.20 |  |  | $ 0.20 |  |  |  |  |  |  |  |
Dividends payable | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 90,749 | $ 90,749 | $ 90,198 | $ 79,771 | $ 79,771 |  |  |  |
Residential whole loans, at fair value | $ | [1] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,381,583 | $ 1,381,583 | $ 1,665,978 |  |  |  |  |  |
Common stock dividends, capital gains (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.1672 | $ 0.1672 | $ 0.1290 | $ 0.0831 | $ 0.0831 |  |  |  |
Common stock, shares authorized (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 886,950,000 | 886,950,000 | 886,950,000 |  |  |  |  |  |
Issuance costs | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 | $ 329 | $ 415 |  |  |  |  |
Number of shares authorized to be repurchased under the Repurchase Program (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10,000,000.0 |  | 4,000,000.0
Number of shares repurchased through the Company's publicly announced stock repurchase program (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  |  |  |
Number of remaining shares authorized to be repurchased under the Repurchase Program (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6,616,355 | 6,616,355 |  |  |  |  |  |  |
DRSPP |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends on Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9,000,000.0 |
Shares of common stock authorized and available for issuance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8,900,000 | 8,900,000 |  |  |  |  |  |  |
Shares issued (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 322,888 | 379,903 | 2,293,192 | 34,378,768 |  |  |  |
Net proceeds | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2,400 | $ 2,800 | $ 18,500 | $ 286,600 |  |  |  |
Series B Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends on Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, cash dividends declared (in dollars per share) | $ / shares |  | $ 0.46875 |  | $ 0.46875 |  | $ 0.46875 |  | $ 0.46875 |  | $ 0.46875 |  | $ 0.46875 |  | $ 0.46875 |  | $ 0.46875 |  | $ 0.46875 |  | $ 0.46875 |  | $ 0.46875 |  | $ 0.46875 |  |  |  |  |  |  |  |  |  |
Preferred Stock | Series B Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends on Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, shares issued (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 8,000,000.0 |  |  |  |  |  |  |  |  |
Preferred stock, dividend rate |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7.50% |  | 7.50% | 7.50% | 7.50% |  |  |  |  |
Preferred stock, par value (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.01 |  |  |  |  |  |  |  |  |
Preferred stock, liquidation preference (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 25.00 | $ 25.00 | $ 25.00 | $ 25 | $ 25 | $ 25 |  |  |  |
Preferred stock, redemption price (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 25.00 |  |  |  |  |  |  |  |  |
Number of additional directors that can be elected by preferred stock holders | director |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 |  |  |  |  |  |  |
At The Market |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends on Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
At-the-market, maximum potential proceeds | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 400,000 |  |  |
Number of shares issued (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,357,526 |  |  |  |  |  |  |
Proceeds from sale of stock | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 9,900 |  |  |  |  |  |  |
Issuance costs | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100 |  |  |  |  |  |  |
Value remaining outstanding for future offerings | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 390,000 | $ 390,000 |  |  |  |  |  |  |
Weighted Average |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends on Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross Proceeds Per Share (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 7.40 | $ 7.40 |  |  |  |  |  |  |
[1] | Includes approximately $186.4 million and $209.4 million of Residential whole loans, at carrying value and $567.4 million and $694.7 million of Residential whole loans, at fair value transferred to consolidated variable interest entities (“VIEs”) at December 31, 2019 and 2018, respectively. Such assets can be used only to settle the obligations of each respective VIE.

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