Basis of Presentation and Summary of Significant Accounting Policies (Narrative, Recent Financial Accounting Standards) (Details) - USD ($) $ in Millions	3 Months Ended
Sep. 30, 2017	Sep. 30, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Facility Exit and Other Costs	$ 128	$ 2

Facility exit and other costs primarily consist of lease termination costs, accelerated depreciation, equipment relocation costs, project consulting fees and costs associated with restructuring our delivery of information technology infrastructure services.

No definition available.

Name:	cah_FacilityExitAndOtherCosts
Namespace Prefix:	cah_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration