Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Income Tax Disclosure [Abstract]
Income before income tax	$ 88,110	$ 107,552	$ 144,083	$ 165,702
Provision for income taxes	$ 25,122	$ 30,920	$ 42,812	$ 59,426
Effective tax rate (as a percent)	28.50%	28.70%	29.70%	35.90%
Unrecognized tax benefits approximate amount of estimated reduction within the next twelve months	$ 11,000		$ 11,000