Income Taxes (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)	$ 4,152
Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Transition Tax For Accumulated Foreign Earnings, Provisional Income Tax Expense	86,707
Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Transition Tax For Accumulated Foreign Earnings, Provisional State Income Tax Expense	1,423
Unremitted foreign earnings	1,228,170
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Provisional Expense for Undistributed Accumulated Earnings of Foreign Subsidiary	6,932
Foreign earnings repatriated	7,250
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Liability, Current	6,937
Long-term tax liability	79,770	$ 0
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Liability, Noncurrent, Due in Year Two, Three, Four, Five	6,937
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Liability, Noncurrent, Due in Year Six	13,005
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Liability, Noncurrent, Due in Year Seven	17,341
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Liability, Noncurrent, Due in Year Eight	$ 21,676