Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Line Items]
Capital loss carry-forwards	$ 22,111	$ 4,602	$ 22,111	$ 4,602
Foreign provision for income taxes			102,824	64,252	$ 25,139
Undistributed earnings	484,510		484,510
Unrecognized deferred tax liability related to temporary differences	8,799		8,799
Earnings retained by subsidiaries and equity accounted investments			484,510	469,000	450,000
Gross unrecognized tax benefits	22,584	25,910	22,584	25,910	$ 19,262
Unrecognized tax benefits that would impact effective tax rate	10,556	13,737	10,556	13,737
Accrued interest and penalties	4,170	3,677	4,170	3,677
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit)	203	9,734
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Change in Tax Rate, Deferred Tax Asset, Provisional Income Tax Expense (Benefit)	10,017	10,070
Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Transition Tax for Accumulated Foreign Earnings, Provisional Liability	486	336	486	336
Capital Loss Carryforward [Member]
Income Tax Disclosure [Line Items]
Capital loss carry-forwards	$ 9,292	$ 11,343	$ 9,292	$ 11,343