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 provision for income taxes	$ 46,340	$ 30,622	$ 82,096	$ 64,970
Income tax expense using estimated annual effective income tax rate	18,793	11,347	33,317	24,145
Changes in effective tax rates	210	(78)	0	0
Impact of discrete items, net	0	(91)	49	(100)
Income tax expense	$ 19,003	$ 11,178	$ 33,366	$ 24,045