Income Taxes Schedule of Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current:
Federal	$ 138,432	$ 144,924	$ 115,150
State	25,952	24,052	20,869
Foreign	32,931	29,046	23,906
Current income tax expense, total	197,315	198,022	159,925
Deferred:
Federal	22,233	9,321	6,225
State	1,212	(179)	(550)
Foreign	(1,057)	(2,900)	(1,396)
Deferred income tax expense, total	22,388	6,242	4,279
Provision for income taxes	$ 219,703	$ 204,264	$ 164,204