Segment Information (Revenue by Reportable Segment) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting Information [Line Items]
Total revenue	$ 39,157	$ 35,228	$ 116,233	$ 108,181
Operating Segments
Segment Reporting Information [Line Items]
Total revenue	39,163	35,232	116,245	108,194
Operating Segments | Pharmaceutical
Segment Reporting Information [Line Items]
Total revenue	35,112	31,361	104,254	96,516
Operating Segments | Medical
Segment Reporting Information [Line Items]
Total revenue	4,051	3,871	11,991	11,678
Corporate
Segment Reporting Information [Line Items]
Total revenue	(6)	(4)	(12)	(13)
Pharmaceutical Distribution and Specialty [Member] | Operating Segments | Pharmaceutical
Segment Reporting Information [Line Items]
Total revenue	34,899	31,146	103,612	95,888
Nuclear Precision Health Services [Member] | Operating Segments | Pharmaceutical
Segment Reporting Information [Line Items]
Total revenue	213	215	642	628
Medical distribution and products [Member] | Operating Segments | Medical
Segment Reporting Information [Line Items]
Total revenue	3,539	3,431	10,483	10,339
Cardinal Health At Home [Member] | Operating Segments | Medical
Segment Reporting Information [Line Items]
Total revenue	$ 512	$ 440	$ 1,508	$ 1,339