Impact of Stock Options and Restricted Stock Awards on Net Income (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Total stock-based compensation		$ 7,236	$ 6,328	$ 12,097	$ 10,727
Tax impact	[1]	(3,517)	1,854	(1,863)	1,448
Reduction in net income, net of tax		$ 3,719	$ 8,182	$ 10,234	$ 12,175

[1] Tax impact is determined at the Company's combined effective tax rate, which includes the statements of operations line item "Increase in income tax benefit payable to former stockholder" (see Note 10).