Condensed Consolidated Statements of Changes in Stockholders' Equity - 9 months ended Sep. 30, 2015 - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Treasury Stock, at Cost [Member]
Beginning Balance at Dec. 31, 2014	$ 579,535	$ 902	$ 655,471	$ 33,516	$ (483)	$ (109,871)
Beginning Balance, shares at Dec. 31, 2014	90,191,100	90,191,100
Equity-based compensation	$ 4,800		4,800
Unrealized loss on derivatives, net of tax	(15,360)				(15,360)
Vesting of restricted shares		$ 1	(1)
Vesting of restricted shares, shares		156,733
Shares withheld for tax withholdings	(838)		(838)
Shares withheld for tax withholdings, shares		(41,945)
Cash dividends declared to stockholders, net of forfeitures	(72,593)		(36,388)	(36,205)
Repurchase of shares of treasury stock, at cost	(15,000)					(15,000)
Net income	60,161			60,161
Ending Balance at Sep. 30, 2015	$ 540,705	$ 903	$ 623,044	$ 57,472	$ (15,843)	$ (124,871)
Ending Balance, shares at Sep. 30, 2015	90,305,888	90,305,888