Segment, Geographic and Revenue Information - Net Revenues by Region (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information
Net revenues	$ 10,032	$ 9,872	$ 30,562	$ 31,559
Americas
Segment Reporting Information
Net revenues	7,489	7,357	22,336	22,989
EMEA
Segment Reporting Information
Net revenues	1,409	1,355	4,687	4,892
Asia
Segment Reporting Information
Net revenues	$ 1,134	$ 1,160	$ 3,539	$ 3,678