Consolidated Balance Sheets (Parenthetical) Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Mortgage-backed securities (including pledged of $2,173,333 and $2,467,859, respectively), at fair value	$ 2,173,333	$ 2,467,859
Preferred Stock, Shares Authorized	50,000,000	50,000,000
Preferred Stock, Shares Outstanding	4,460,000	7,248,330
Preferred Stock, Shares Issued	4,460,000	7,248,330
Preferred Stock, Liquidation Preference, Value	$ 111,500	$ 181,208
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	90,000,000	90,000,000
Common Stock, Shares, Issued	30,879,569	23,697,970
Common Stock, Shares, Outstanding	30,879,569	23,697,970
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01