CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Residential whole loans, at carrying value	$ 4,847,782,000	$ 1,645,372,000
Residential whole loans, at fair value	794,684,000	738,638,000
MSR Related Assets, pledged as collateral	$ 1,217,002,000	$ 611,807,000
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	8,050,000	8,050,000
Preferred stock, dividend rate	7.50%	7.50%
Preferred stock, shares issued (in shares)	8,000,000	8,000,000
Preferred stock, shares outstanding (in shares)	8,000,000	8,000,000
Preferred stock, aggregate liquidation preference (in dollars)	$ 200,000,000	$ 200,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	886,950,000	886,950,000
Common stock, shares issued (in shares)	452,369,000	449,787,000
Common stock, shares outstanding (in shares)	452,369,000	449,787,000
Collateral Pledged | Agency MBS
Securities, at fair value, pledged as collateral	$ 1,658,614,000	$ 2,575,331,000
Collateral Pledged | Non-Agency MBS
Securities, at fair value, pledged as collateral	2,055,802,000	3,248,900,000
Collateral Pledged | CRT securities
Securities, at fair value, pledged as collateral	$ 252,175,000	$ 480,315,000