CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Common Stock Shares Outstanding	Common Stock	Additional Paid-In Capital	Accum. Other Comp. Income Gain Agency MBS	Accum. Other Comp. Income Non-Agency MBS	Accum. Other Comp. Gain (Loss) Derivatives	Accum. (Deficit) Series A Preferred Stock	Accum. (Deficit) Series B Preferred Stock	Accum. (Deficit) Series C Preferred Stock	Accum. (Deficit)	Series A Preferred Stock Shares Outstanding	Series C Preferred Stock Shares Outstanding	Series A Preferred Stock	Series B Preferred Stock	Series C Preferred Stock	Total
Beginning Balance at Dec. 31, 2017		$ 981	$ 980,243	$ 2,163	$ 30,201	$ (15,344)				$ (415,235)			$ 46,537		$ 48,420	$ 677,967
Beginning Balance (in shares) at Dec. 31, 2017	98,137										1,919	1,989
Issuance of Preferred Stock															524	524
Issuance of Preferred Stock (in shares)												21
Issuance of stock		1	365													366
Issuance of stock (in shares)	75
Other comprehensive income, fair value adjustments and reclassifications				(23,536)	709	746										(22,081)
Net (loss) income										(2,853)						(2,853)
Amortization of restricted stock			24													24
Dividends on preferred stock							$ (1,035)	$ (305)	$ (958)				(1,035)	$ (305)	(958)
Dividend declared per common share										(14,732)						(14,732)
Ending Balance at Mar. 31, 2018		982	980,632	(21,373)	30,910	(14,598)				(435,118)			46,537		48,944	636,917
Ending Balance (in shares) at Mar. 31, 2018	98,212										1,919	2,010
Beginning Balance at Dec. 31, 2017		981	980,243	2,163	30,201	(15,344)				(415,235)			46,537		48,420	677,967
Beginning Balance (in shares) at Dec. 31, 2017	98,137										1,919	1,989
Other comprehensive income, fair value adjustments and reclassifications																(58,117)
Net (loss) income																29,445
Dividends on preferred stock																(6,892)
Ending Balance at Sep. 30, 2018		984	981,499	(51,894)	23,347	(12,550)				(434,950)			46,537		48,944	601,918
Ending Balance (in shares) at Sep. 30, 2018	98,381										1,919	2,010
Beginning Balance at Mar. 31, 2018		982	980,632	(21,373)	30,910	(14,598)				(435,118)			46,537		48,944	636,917
Beginning Balance (in shares) at Mar. 31, 2018	98,212										1,919	2,010
Issuance of stock		1	430													431
Issuance of stock (in shares)	92
Other comprehensive income, fair value adjustments and reclassifications				(13,847)	(1,558)	1,005										(14,400)
Net (loss) income										14,933						14,933
Amortization of restricted stock			25													25
Dividends on preferred stock							(1,035)	(305)	(957)				(1,035)	(305)	(957)
Dividend declared per common share										(13,763)						(13,763)
Ending Balance at Jun. 30, 2018		983	981,087	(35,220)	29,352	(13,593)				(436,245)			46,537		48,944	621,846
Ending Balance (in shares) at Jun. 30, 2018	98,304										1,919	2,010
Issuance of stock		1	387													388
Issuance of stock (in shares)	77
Other comprehensive income, fair value adjustments and reclassifications				(16,674)	(6,005)	1,043										(21,636)
Net (loss) income										17,365						17,365
Amortization of restricted stock			25													25
Dividends on preferred stock							(1,035)	(305)	(958)				(1,035)	(305)	(958)	(2,297)
Dividend declared per common share										(13,772)						(13,772)
Ending Balance at Sep. 30, 2018		984	981,499	(51,894)	23,347	(12,550)				(434,950)			46,537		48,944	601,918
Ending Balance (in shares) at Sep. 30, 2018	98,381										1,919	2,010
Beginning Balance at Dec. 31, 2018		985	981,964	(28,824)	9,563	(11,531)				(485,988)			46,537		48,944	561,650
Beginning Balance (in shares) at Dec. 31, 2018	98,483										1,919	2,010
Issuance of stock		1	355													356
Issuance of stock (in shares)	82
Other comprehensive income, fair value adjustments and reclassifications				31,278	8,165	1,003										40,446
Net (loss) income										(19,970)						(19,970)
Amortization of restricted stock			25													25
Dividends on preferred stock							(1,035)	(304)	(958)				(1,035)	(304)	(958)
Dividend declared per common share										(12,815)						(12,815)
Ending Balance at Mar. 31, 2019		986	982,344	2,454	17,728	(10,528)				(521,070)			46,537		48,944	567,395
Ending Balance (in shares) at Mar. 31, 2019	98,565										1,919	2,010
Beginning Balance at Dec. 31, 2018		985	981,964	(28,824)	9,563	(11,531)				(485,988)			46,537		48,944	561,650
Beginning Balance (in shares) at Dec. 31, 2018	98,483										1,919	2,010
Other comprehensive income, fair value adjustments and reclassifications																97,742
Net (loss) income																(85,162)
Dividends on preferred stock																(6,892)
Ending Balance at Sep. 30, 2019		988	983,124	41,629	33,867	(8,546)				(611,588)			46,537		48,626	534,637
Ending Balance (in shares) at Sep. 30, 2019	98,768										1,919	2,010
Beginning Balance at Mar. 31, 2019		986	982,344	2,454	17,728	(10,528)				(521,070)			46,537		48,944	567,395
Beginning Balance (in shares) at Mar. 31, 2019	98,565										1,919	2,010
Issuance of stock		1	401													402
Issuance of stock (in shares)	118
Other comprehensive income, fair value adjustments and reclassifications				28,378	9,571	1,011										38,960
Net (loss) income										(47,700)						(47,700)
Amortization of restricted stock			25													25
Amortization of shelf offering expenses															(318)	(318)
Dividends on preferred stock							(1,035)	(304)	(958)				(1,035)	(304)	(958)
Dividend declared per common share										(10,855)						(10,855)
Ending Balance at Jun. 30, 2019		987	982,770	30,832	27,299	(9,517)				(581,922)			46,537		48,626	545,612
Ending Balance (in shares) at Jun. 30, 2019	98,683										1,919	2,010
Issuance of stock	$ 85	1	329													330
Other comprehensive income, fair value adjustments and reclassifications				10,797	6,568	971										18,336
Net (loss) income										(17,492)						(17,492)
Amortization of restricted stock			25													25
Dividends on preferred stock							$ (1,035)	$ (304)	$ (958)				(1,035)	$ (304)	(958)	(2,297)
Dividend declared per common share										(9,877)						(9,877)
Ending Balance at Sep. 30, 2019		$ 988	$ 983,124	$ 41,629	$ 33,867	$ (8,546)				$ (611,588)			$ 46,537		$ 48,626	$ 534,637
Ending Balance (in shares) at Sep. 30, 2019	98,768										1,919	2,010