CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
MBS and GSE CRT pledged as collateral	$ 7,326,175,000	$ 7,614,935,000
Allowance for credit losses	$ 0	$ 1,768,000
Preferred Stock, par value (in usd per share)	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	50,000,000	50,000,000
Common stock, par value (in usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized	450,000,000	450,000,000
Common stock, shares issued	329,874,780	203,222,108
Common stock, shares outstanding	329,874,780	203,222,108
Series A Preferred Stock
Preferred Stock, dividend rate stated percentage	7.75%	7.75%
Preferred Stock, shares issued	0	5,600,000
Preferred Stock, shares outstanding	0	5,600,000
Preferred Stock, aggregate liquidation preference		$ 140,000,000
Series B Preferred Stock
Preferred Stock, dividend rate stated percentage	7.75%	7.75%
Preferred Stock, shares issued	6,200,000	6,200,000
Preferred Stock, shares outstanding	6,200,000	6,200,000
Preferred Stock, aggregate liquidation preference	$ 155,000,000	$ 155,000,000
Series C Preferred Stock
Preferred Stock, dividend rate stated percentage	7.50%	7.50%
Preferred Stock, shares issued	11,500,000	11,500,000
Preferred Stock, shares outstanding	11,500,000	11,500,000
Preferred Stock, aggregate liquidation preference	$ 287,500,000	$ 287,500,000