Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Tax Contingency [Line Items]
tax payable for the transition tax on foreign unremitted earnings	$ 38,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate	21.00%
Unrecognized Tax Benefits	$ 35,879	$ 24,361	$ 31,534	$ 36,935
Unrecognized Tax Benefits, Interest on Income Taxes Expense	945	(2,792)	(1,946)
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	4,189	3,301
Deferred Tax Liabilities, Undistributed Foreign Earnings	4,800,000
Income Taxes Paid, Net	226,422	$ 231,183	$ 190,109
International [Member]
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Amount	391,598
Tax Credit Carryforward, Subject to Expiration	26,663
Tax Credit Carryforward, No Expiration	364,935
Tax Credit Carryforward, Deferred Tax Asset	120,148
Other Tax Carryforward, Valuation Allowance	$ 7,533