Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Income tax expense	$ 58,543	$ 61,254
Effective tax rate	33.00%	33.00%
Federal statutory rate	35.00%	35.00%
State income tax expense	$ 3,215	$ 3,834
Undistributed Earnings of Foreign Subsidiaries	3,465	5,262
Effective Income Tax Rate Reconciliation, Deduction, Qualified Production Activity, Amount	5,322	5,168
Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount	2,000	$ 2,831
Deferred Tax Assets, Tax Credit Carryforwards, Foreign	43,000
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation	852
Second component of tax deductible goodwill, net of tax	$ 400