Description of Business and Basis of Consolidation and Presentation (Details) $ in Millions	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) segment	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment				3
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Income tax expense reduction	$ (45)		$ 48	$ (208)	$ (25)
Initial Recognition of Global Intangible Low-taxed Income of Foreign Subsidiaries
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Income tax expense reduction		$ 35				$ 35