Revenue from Contracts with Customers - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 29, 2018
Disaggregation of Revenue [Line Items]
Net sales	$ 1,121	$ 1,126	$ 1,026	$ 1,065	$ 1,008	$ 1,018	$ 1,009	$ 941	$ 4,339	$ 3,976	$ 3,778
Product and services eliminations
Disaggregation of Revenue [Line Items]
Net sales									(89)	(47)	(12)
Geography Eliminations
Disaggregation of Revenue [Line Items]
Net sales									(11)	(12)	(11)
North America
Disaggregation of Revenue [Line Items]
Net sales									2,377	2,111	1,939
North America | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									2,377	2,111	1,939
North America | Product and services eliminations
Disaggregation of Revenue [Line Items]
Net sales									(76)	(33)	(2)
Europe
Disaggregation of Revenue [Line Items]
Net sales									1,571	1,509	1,463
Europe | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									1,571	1,509	1,463
Europe | Product and services eliminations
Disaggregation of Revenue [Line Items]
Net sales									(13)	(14)	(10)
APAC & Emerging Markets
Disaggregation of Revenue [Line Items]
Net sales									402	368	387
APAC & Emerging Markets | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									402	368	387
APAC & Emerging Markets | Product and services eliminations
Disaggregation of Revenue [Line Items]
Net sales									0	0	0
Supply Chain Services | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									3,926	3,678	3,689
Supply Chain Services | Geography Eliminations
Disaggregation of Revenue [Line Items]
Net sales									(11)	(12)	(11)
Supply Chain Services | North America | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									1,969	1,816	1,858
Supply Chain Services | Europe | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									1,574	1,513	1,462
Supply Chain Services | APAC & Emerging Markets | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									394	361	380
Software Services | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									96	99	101
Software Services | Geography Eliminations
Disaggregation of Revenue [Line Items]
Net sales									0	0	0
Software Services | North America | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									78	82	83
Software Services | Europe | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									10	10	11
Software Services | APAC & Emerging Markets | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									8	7	7
Prescription Management | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									406	246	0
Prescription Management | Geography Eliminations
Disaggregation of Revenue [Line Items]
Net sales									0	0	0
Prescription Management | North America | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									406	246	0
Prescription Management | Europe | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									0	0	0
Prescription Management | APAC & Emerging Markets | Operating Segments
Disaggregation of Revenue [Line Items]
Net sales									$ 0	$ 0	$ 0