Segment Information (Revenue by Reportable Segment) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Segment Reporting Information [Line Items]
Total revenue	$ 39,275	$ 39,157	$ 119,881	$ 116,233
Operating Segments
Segment Reporting Information [Line Items]
Total revenue	39,278	39,163	119,893	116,245
Operating Segments | Pharmaceutical
Segment Reporting Information [Line Items]
Total revenue	35,104	35,112	107,452	104,254
Operating Segments | Medical
Segment Reporting Information [Line Items]
Total revenue	4,174	4,051	12,441	11,991
Corporate
Segment Reporting Information [Line Items]
Total revenue	(3)	(6)	(12)	(12)
Pharmaceutical Distribution and Specialty [Member] | Operating Segments | Pharmaceutical
Segment Reporting Information [Line Items]
Total revenue	34,903	34,899	106,859	103,612
Nuclear Precision Health Services [Member] | Operating Segments | Pharmaceutical
Segment Reporting Information [Line Items]
Total revenue	201	213	593	642
Medical distribution and products [Member] | Operating Segments | Medical
Segment Reporting Information [Line Items]
Total revenue	3,638	3,539	10,805	10,483
Cardinal Health At Home [Member] | Operating Segments | Medical
Segment Reporting Information [Line Items]
Total revenue	$ 536	$ 512	$ 1,636	$ 1,508