Income Taxes Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2018
Operating Loss Carryforwards [Line Items]
Effective Income Tax Rate	20.80%	13.90%
Non-US [Member]
Operating Loss Carryforwards [Line Items]
Deferred Foreign Income Tax Expense/(Benefit) Expected	$ 235