Consolidated Statements of Shareholders' Equity Statement - USD ($) $ in Thousands	Total	Preferred Stock	Preferred Stock Including Additional Paid in Capital	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Balance at Dec. 31, 2015	$ 492,025		$ 109,658	$ 490	$ 725,358	$ (12,768)	$ (330,713)
Balance, Preferred shares outstanding at Dec. 31, 2015		4,550,000
Balance, Common shares outstanding at Dec. 31, 2015				49,047,335
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Shares, New Issues		21,937		20,582
Stock Issued During Period, Shares, Restricted Stock Award, Gross				214,878
Shares Paid for Tax Withholding for Share Based Compensation				80,888
Stock issuance	685		548	$ 1	136
Restricted stock granted, net of amortization	2,709			2	2,707
Adjustments for tax withholding on share-based compensation	(485)			$ (1)	(484)
Stock issuance costs	(239)		(201)		(38)
Stock Repurchased During Period, Shares				(48,444)
Stock Repurchased During Period, Value	(310)				310
Net income	43,099						43,099
Dividends on preferred stock	(9,185)						(9,185)
Dividends on common stock	(41,274)						(41,274)
Other comprehensive income (loss)	(19,841)					(19,841)
Balance at Dec. 31, 2016	467,184		110,005	$ 492	727,369	(32,609)	(338,073)
Balance, Preferred shares outstanding at Dec. 31, 2016		4,571,937
Balance, Common shares outstanding at Dec. 31, 2016				49,153,463
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Shares, New Issues		1,316,743		6,617,487
Stock Issued During Period, Shares, Restricted Stock Award, Gross				138,166
Shares Paid for Tax Withholding for Share Based Compensation				77,567
Stock issuance	78,532		31,350	$ 66	47,116
Restricted stock granted, net of amortization	1,954			1	1,953
Adjustments for tax withholding on share-based compensation	(521)			(1)	(520)
Stock issuance costs	(106)		(61)		(45)
Net income	33,893						33,893
Dividends on preferred stock	(10,794)						(10,794)
Dividends on common stock	(36,996)						(36,996)
Other comprehensive income (loss)	23,912					23,912
Balance at Dec. 31, 2017	$ 557,058		141,294	$ 558	775,873	(8,697)	(351,970)
Balance, Preferred shares outstanding at Dec. 31, 2017	5,888,680	5,888,680
Balance, Common shares outstanding at Dec. 31, 2017	55,831,549			55,831,549
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued During Period, Shares, New Issues		65,914		6,829,647
Stock Issued During Period, Shares, Restricted Stock Award, Gross				213,157
Shares Paid for Tax Withholding for Share Based Compensation				57,135
Stock issuance	$ 43,457		1,599	$ 69	41,789
Restricted stock granted, net of amortization	1,230			2	1,228
Adjustments for tax withholding on share-based compensation	(364)			(1)	(363)
Stock issuance costs	(95)		(10)		(85)
Net income	7,023						7,023
Dividends on preferred stock	(11,801)						(11,801)
Dividends on common stock	(42,273)						(42,273)
Other comprehensive income (loss)	(27,082)					(27,082)
Balance at Dec. 31, 2018	$ 527,153		$ 142,883	$ 628	$ 818,442	$ (35,779)	$ (399,021)
Balance, Preferred shares outstanding at Dec. 31, 2018	5,954,594	5,954,594
Balance, Common shares outstanding at Dec. 31, 2018	62,817,218			62,817,218