Business Segments - Segment Assets (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Assets	$ 17,185	$ 16,872
Operating Segments
Segment Reporting Information [Line Items]
Assets	15,041	14,571
Operating Segments | Americas
Segment Reporting Information [Line Items]
Assets	7,606	7,160
Operating Segments | Europe, Middle East and Africa
Segment Reporting Information [Line Items]
Assets	4,724	4,809
Operating Segments | Asia Pacific
Segment Reporting Information [Line Items]
Assets	2,711	2,602
Corporate
Segment Reporting Information [Line Items]
Assets	$ 2,144	$ 2,301