Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
excess tax benefits from share-based compensation		$ 5,400	$ 4,300	$ 400
Tax Cuts And Jobs Act Of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)	$ 87,000	(4,800)
Tax expense/(benefit) related to changes in pension and post-retirement plan assets and benefit obligations	3,500	(7,100)	3,500	(8,400)
Unrealized tax asset on related tax loss		101,200	99,700
Valuation allowance against U.S. and non-U.S. deferred tax assets		23,100	23,300
Total valuation allowance	123,000	124,300	123,000
Increase in total amount of unrecognized tax benefits that would impact effective tax rate	49,200	43,100	49,200	47,600
Interest expense and penalties, related to unrecognized tax benefits		700	300	$ 400
Unrecognized tax benefits, income tax penalties and interest accrued	$ 6,500	7,200	$ 6,500
Change in unrecognized tax benefits is reasonably possible, amount of unrecorded benefit		6,800
Undistributed Earnings of Foreign Subsidiaries		232,400
Undistributed Foreign Earnings, Not Permanently Reinvested		1,168,700
Undistributed Foreign Earnings, Not Permanently Reinvested, Tax		$ 7,500