- Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Net sales	$ 1,065	$ 941
North America
Disaggregation of Revenue [Line Items]
Net sales	550	497
Europe
Disaggregation of Revenue [Line Items]
Net sales	422	361
APAC & Emerging Markets
Disaggregation of Revenue [Line Items]
Net sales	95	86
Operating Segments | North America
Disaggregation of Revenue [Line Items]
Net sales	550	497
Operating Segments | Europe
Disaggregation of Revenue [Line Items]
Net sales	422	361
Operating Segments | APAC & Emerging Markets
Disaggregation of Revenue [Line Items]
Net sales	95	86
Operating Segments | Supply Chain Services
Disaggregation of Revenue [Line Items]
Net sales	977	885
Operating Segments | Supply Chain Services | North America
Disaggregation of Revenue [Line Items]
Net sales	462	442
Operating Segments | Supply Chain Services | Europe
Disaggregation of Revenue [Line Items]
Net sales	424	362
Operating Segments | Supply Chain Services | APAC & Emerging Markets
Disaggregation of Revenue [Line Items]
Net sales	93	84
Operating Segments | Software Solutions
Disaggregation of Revenue [Line Items]
Net sales	24	26
Operating Segments | Software Solutions | North America
Disaggregation of Revenue [Line Items]
Net sales	20	22
Operating Segments | Software Solutions | Europe
Disaggregation of Revenue [Line Items]
Net sales	2	2
Operating Segments | Software Solutions | APAC & Emerging Markets
Disaggregation of Revenue [Line Items]
Net sales	2	2
Operating Segments | Prescription Management
Disaggregation of Revenue [Line Items]
Net sales	84	34
Operating Segments | Prescription Management | North America
Disaggregation of Revenue [Line Items]
Net sales	84	34
Operating Segments | Prescription Management | Europe
Disaggregation of Revenue [Line Items]
Net sales	0	0
Operating Segments | Prescription Management | APAC & Emerging Markets
Disaggregation of Revenue [Line Items]
Net sales	0	0
Eliminations
Disaggregation of Revenue [Line Items]
Net sales	(20)	(4)
Eliminations | North America
Disaggregation of Revenue [Line Items]
Net sales	(16)	(1)
Eliminations | Europe
Disaggregation of Revenue [Line Items]
Net sales	(4)	(3)
Eliminations | APAC & Emerging Markets
Disaggregation of Revenue [Line Items]
Net sales	0	0
Eliminations
Disaggregation of Revenue [Line Items]
Net sales	(2)	(3)
Eliminations | Supply Chain Services
Disaggregation of Revenue [Line Items]
Net sales	(2)	(3)
Eliminations | Software Solutions
Disaggregation of Revenue [Line Items]
Net sales	0	0
Eliminations | Prescription Management
Disaggregation of Revenue [Line Items]
Net sales	$ 0	$ 0