Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Income before provision for income taxes	$ 35,756	$ 34,348
Income tax expense using estimated annual effective income tax rate	14,314	12,965
Impact of discrete items, net	49	(98)
Income tax expense	$ 14,363	$ 12,867