Segment Information (Narrative) (Details) $ in Millions	12 Months Ended
Jun. 30, 2023 USD ($) segment	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments \| segment	2
Project costs on investment and other spending	$ 35	$ 50	$ 27
Total Opioid Litigation [Member]
Segment Reporting Information [Line Items]
Litigation Settlement, Expense			$ 1,170

Investment spending at the Corporate level. Investment spending generally includes the first year spend for certain projects that require incremental investments in the form of additional operating expenses.

No definition available.

+ Details

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Namespace Prefix:	cah_
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Balance Type:	debit
Period Type:	duration

- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482810/280-10-50-18

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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