Business Combinations (Pro Forma) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Business Acquisition, Pro Forma Information
Revenue	$ 64,712	$ 51,476	$ 128,465	$ 102,880
Net income	$ 19,036	$ 13,579	$ 37,372	$ 28,996
Basic EPS	$ 0.54	$ 0.35	$ 1.06	$ 0.76
Diluted EPS	$ 0.54	$ 0.35	$ 1.05	$ 0.75
Revenue, Net, Increase (Decrease)	$ 13,236		$ 25,585
Revenue, Net, Increase (Decrease), Percentage	25.70%		24.90%
Parent, Qatarlyst, Curepet , Healthcare Magic Combined [Member]
Business Acquisition, Pro Forma Information
Business Acquisition, Pro Forma Revenue, Increase (Decrease), Percentage			(3.10%)
Parent, Curepet , Healthcare Magic, Vertex, Oakstone, and i3 Combined [Member]
Business Acquisition, Pro Forma Information
Revenue, pro forma	$ 68,813	$ 70,351	$ 135,218	$ 139,519
Net income, pro forma	$ 19,616	$ 13,796	$ 37,602	$ 28,910
Basic EPS, pro forma	$ 0.56	$ 0.36	$ 1.06	$ 0.75
Diluted EPS, pro forma	$ 0.56	$ 0.36	$ 1.06	$ 0.75
Business Acquisition, Pro Forma Revenue, Increase (Decrease)	$ (1,538)		$ (4,301)
Business Acquisition, Pro Forma Revenue, Increase (Decrease), Percentage	(2.20%)