Consolidated Statements of Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Interest income	$ 110,051	$ 94,502	$ 91,898
Interest expense	59,574	36,178	25,231
Net interest income	50,477	58,324	66,667
(Loss) gain on derivative instruments, net	(3,461)	3,044	(5,606)
Loss on sale of investments, net	(23,373)	(11,530)	(4,238)
Fair value adjustments, net	(52)	(75)	(103)
Other operating (expense) income, net	(1,567)	(201)	880
General and administrative expenses:
Compensation and benefits	(6,605)	(8,509)	(7,550)
Other general and administrative	(8,500)	(7,310)	(7,157)
Net income	7,023	33,893	43,099
Preferred stock dividends	11,801	10,794	9,185
Net (loss) income to common shareholders	(4,778)	23,099	33,914
Other comprehensive income:
Unrealized (loss) gain on available-for-sale investments, net	(50,218)	12,650	(23,828)
Reclassification adjustment for loss on sale of investments, net	23,373	11,530	4,238
Reclassification adjustment for de-designated cash flow hedges	(237)	(268)	(251)
Total other comprehensive (loss) income	(27,082)	23,912	(19,841)
Comprehensive (loss) income to common shareholders	$ (31,860)	$ 47,011	$ 14,073
Net (loss) income per common share-basic and diluted	$ (0.08)	$ 0.46	$ 0.69
Weighted average common shares-basic and diluted	57,705	50,417	49,114