Income Taxes (Net Operating Loss Carryforwards and Tax Credit Carryforwards Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
Tax Credit Carryforward, Amount	$ 301
Tax Credit Carryforward, Valuation Allowance	277
Alternative Minimum Tax Credit Carryforwards, Before Tax	$ 21
Tax Credit Carryforward, Expiration Date	Dec. 31, 2027
US Federal [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 33
State [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	73
Valuation allowance offset for State net operating loss carryforwards due to uncertain recoverability	65
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	2,100
Tax Credit Carryforward, Valuation Allowance		$ 164
CHINA
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	$ 450
Minimum [Member] | US Federal [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward expiration	Dec. 31, 2021
Minimum [Member] | CHINA
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward expiration	Dec. 31, 2019
Maximum [Member] | CHINA
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward expiration	Dec. 31, 2021