CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands, except Share data	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]	Noncontrolling Interest [Member]	Total
Balances at Dec. 31, 2011	$ 2	$ 128,183	$ (3,381)	$ 105,232	$ 18,700	$ 248,736
Balances (shares) at Dec. 31, 2011	19,295,000
Net income				63,465	816	64,281
Foreign currency translation adjustments			464			464
Deconsolidation of non-controlling interest		49			(19,516)	(19,467)
Issuance of common stock, net of underwriting discount and offering expenses		51,543				51,543
Issuance of common stock, net of underwriting discount and offering expenses (in shares)	2,757,000					2,757,170
Stock based compensation		1,288				1,288
Balances at Dec. 31, 2012	2	181,063	(2,917)	168,697		346,845
Balances (shares) at Dec. 31, 2012	22,052,000
Net income				63,926	594	64,520
Foreign currency translation adjustments			561			561
Exercise of stock options		1,524				1,524
Exercise of stock options (shares)	160,000
Stock issuance costs		(155)				(155)
Stock based compensation -options		1,429				1,429
Stock based compensation - restricted stock		107				107
Stock based compensation - restricted stock (shares)	28,000
Excess tax benefit from share-based compensation awards		295				295
Balances at Dec. 31, 2013	2	184,263	(2,356)	232,623	594	415,126
Balances (shares) at Dec. 31, 2013	22,240,000					22,240,673
Net income				60,274	111	60,385
Foreign currency translation adjustments			(3,321)			(3,321)
Repurchase of common stock		(31,395)				(31,395)
Repurchase of common stock (shares)	(1,483,000)
Exercise of stock options		114				114
Exercise of stock options (shares)	7,000
Stock based compensation -options		1,627				1,627
Stock based compensation - restricted stock		258				258
Stock based compensation - restricted stock (shares)	24,000
Excess tax benefit from share-based compensation awards		27				27
Contributions and other					84	84
Balances at Dec. 31, 2014	$ 2	$ 154,894	$ (5,677)	$ 292,897	$ 789	$ 442,905
Balances (shares) at Dec. 31, 2014	20,788,000					20,788,277