Condensed Consolidated Statements of Changes in Stockholders' Equity (USD $) In Thousands, except Share data	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	(Accumulated Deficit) Retained Earnings [Member]	Accumulated Other Comprehensive (Loss) Gain [Member]
Beginning Balance at Dec. 31, 2012	$ 449,848	$ 827	$ 456,923	$ (6,648)	$ (1,254)
Beginning Balance, shares at Dec. 31, 2012		82,737,008
Equity-based compensation	4,704	1	4,703
Equity-based compensation, shares		74,561
Unrealized gain (loss) on derivatives, net of tax	1,453				1,453
Issuance of common stock in initial public offering, net of underwriter commissions and offering costs	245,441	100	245,341
Issuance of common stock in initial public offering, net of underwriter commissions and offering costs, shares		10,000,000
Conversion of common stock into unvested restricted shares		(32)	32
Conversion of common stock into unvested restricted shares, shares		(3,216,719)
Vesting of restricted shares
Vesting of restricted shares, shares		31,675
Dividends declared to stockholders	(36,144)		(18,072)	(18,072)
Net income	63,985			63,985
Ending Balance at Sep. 30, 2013	$ 729,287	$ 896	$ 688,927	$ 39,265	$ 199
Ending Balance, shares at Sep. 30, 2013		89,626,525