CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands	Total	Preferred Stock [Member]	Common Stock [Member]	Additional Paid in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated (Deficit) [Member]
Beginning balance at Dec. 31, 2013	$ 855,498	$ 141,000	$ 9	$ 797,146	$ (21,546)	$ (61,111)
Beginning balance, shares at Dec. 31, 2013		141	87,186
Net income	31,085					31,085
Exercise of stock options, shares			64
Exercise of stock options	703			703
Restricted stock grants, net, shares			304
Restricted stock grants, net	(2,543)			(2,543)
Dividends on preferred stock	(353)					(353)
Other comprehensive (loss) income, net	10,415				10,415
Ending balance at Mar. 31, 2014	894,805	141,000	9	795,306	(11,131)	(30,379)
Ending balance, shares at Mar. 31, 2014		141	87,554
Beginning balance at Dec. 31, 2014	1,000,928	70,500	9	828,327	16,639	85,453
Beginning balance, shares at Dec. 31, 2014		71	88,691
Net income	40,190					40,190
Exercise of stock options, shares			51
Exercise of stock options	793			793
Restricted stock grants, net, shares			438
Restricted stock grants, net	2,811			2,811
Dividends on preferred stock	(176)					(176)
Other comprehensive (loss) income, net	6,784				6,784
Ending balance at Mar. 31, 2015	$ 1,051,330	$ 70,500	$ 9	$ 831,931	$ 23,423	$ 125,467
Ending balance, shares at Mar. 31, 2015		71	89,180