Restructuring and Asset Impairment Charges - Summary of Details for Charges Recorded (Details) $ in Millions	12 Months Ended
	Mar. 31, 2019 USD ($)
Other
Restructuring Cost and Reserve [Line Items]
Total	$ 91
Strategic Growth Initiative Plan
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	154
Exit-related costs	144
Asset impairments and accelerated depreciation	33
Total	331
Strategic Growth Initiative Plan | Operating Segments | U.S. Pharmaceutical and Specialty Solutions
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	50
Exit-related costs	7
Asset impairments and accelerated depreciation	6
Total	63
Strategic Growth Initiative Plan | Operating Segments | European Pharmaceutical Solutions
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	33
Exit-related costs	3
Asset impairments and accelerated depreciation	5
Total	41
Strategic Growth Initiative Plan | Operating Segments | Medical-Surgical Solutions
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	19
Exit-related costs	20
Asset impairments and accelerated depreciation	3
Total	42
Strategic Growth Initiative Plan | Operating Segments | Other
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	16
Exit-related costs	57
Asset impairments and accelerated depreciation	18
Total	91
Strategic Growth Initiative Plan | Corporate
Restructuring Cost and Reserve [Line Items]
Severance and employee-related costs, net	36
Exit-related costs	57
Asset impairments and accelerated depreciation	1
Total	$ 94