Income Taxes (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Income Tax Disclosure [Abstract]
Effective income tax rate, continuing operations	31.70%	19.40%
Tax expense on gain from commercial settlement		$ 1
Tax benefits related to restructuring expense	$ 7	8
Effective rate reconciliation measurement period adjustments due to the Tax Act		13
Effective income tax reconciliation, other postretirement expense	6
Effective Income Tax Rate Reconciliation, Deduction, Other, Amount	5
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount	$ 22	(10)
Effective Income Tax Rate Reconciliation, Tax Credit, Foreign, Amount		$ 21