Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Assets:
Pledged MBS	$ 4,547,769	$ 3,511,604
Pledged U.S. Treasuries	$ 0	$ 0
Shareholders’ Equity:
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	50,000,000	50,000,000
Preferred stock, shares issued	6,168,062	5,954,594
Preferred stock, shares outstanding	6,168,062	5,954,594
Preferred stock, aggregate liquidation preference	$ 154,202	$ 148,865
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	72,248,126	62,817,218
Common stock, shares outstanding	72,248,126	62,817,218