Adjustment to the fair value of the debt instrument resulting from the termination of interest rate swap.

No definition available.

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

- Definition

Date the debt instrument was offered for sale, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Notional Amount

-URI http://asc.fasb.org/extlink&oid=6519104

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5580258-113959

+ Details

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Balance Type:	na
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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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Period Type:	duration

- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Financial Instruments (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2014	Jun. 30, 2015	Jun. 30, 2014
Derivative [Line Items]
Debt instrument, offering date		Nov. 07, 2014
Fair value adjustment related to previously terminated swaps	$ 22
Fair Value Hedging \| Interest Rate Swaps
Derivative [Line Items]
Derivative, notional amount		$ 1,613	$ 1,438
Cash Flow Hedging \| Interest Rate Swaps
Derivative [Line Items]
Derivative, notional amount			300
Designated as Hedging Instrument \| Fair Value Hedging \| Interest Rate Swaps
Derivative [Line Items]
Derivative, notional amount		1,050	300
Designated as Hedging Instrument \| Cash Flow Hedging \| Interest Rate Swaps
Derivative [Line Items]
Derivative, notional amount		1,150
Debt Offering 2015 \| Designated as Hedging Instrument \| Fair Value Hedging \| Interest Rate Swaps
Derivative [Line Items]
Derivative, notional amount		250
Debt Offering 2014 \| Designated as Hedging Instrument \| Fair Value Hedging \| Interest Rate Swaps
Derivative [Line Items]
Derivative, notional amount		450
Debt Redemption \| Designated as Hedging Instrument \| Fair Value Hedging \| Interest Rate Swaps
Derivative [Line Items]
Derivative, notional amount		875
Forward Contracts \| Designated as Hedging Instrument \| Cash Flow Hedging \| Interest Rate Swaps
Derivative [Line Items]
Derivative, notional amount		$ 850	$ 50
Minimum \| Fair Value Hedging \| Interest Rate Swaps
Derivative [Line Items]
Derivative, maturity date		Jun. 15, 2017	Jun. 15, 2015
Minimum \| Cash Flow Hedging \| Interest Rate Swaps
Derivative [Line Items]
Derivative, maturity date			Jun. 15, 2025
Maximum \| Fair Value Hedging \| Interest Rate Swaps
Derivative [Line Items]
Derivative, maturity date		Jun. 15, 2022	Jun. 15, 2022
Maximum \| Cash Flow Hedging \| Interest Rate Swaps
Derivative [Line Items]
Derivative, maturity date			Oct. 17, 2026