Amount of fee for early termination of credit facility.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Maximum ratio of total debt to total capitalization (total debt plus total equity plus redeemable noncontrolling interest) allowed under credit agreement

+ References

No definition available.

+ Details

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Namespace Prefix:	apd_
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Period Type:	instant

- 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

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	instant

- Details

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- Details

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- Details

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- Details

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Period Type:

- Details

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- Details

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Debt (Narrative) (Details) - USD ($)			6 Months Ended
Debt (Narrative) (Details) - USD ($)	Mar. 31, 2021	Mar. 30, 2021	Mar. 31, 2021	Sep. 30, 2020
Revolving credit agreement \| 2021 Credit Agreement
Debt Instrument [Line Items]
Term of credit facility (in years)	5 years
Maximum borrowing capacity	$ 2,500,000,000		$ 2,500,000,000
Borrowings outstanding	$ 0		$ 0
Revolving credit agreement \| 2021 Credit Agreement \| Maximum
Debt Instrument [Line Items]
Debt covenant, maximum ratio of total debt to capitalization	70.00%		70.00%
Revolving credit agreement \| 2017 Credit Agreement
Debt Instrument [Line Items]
Term of credit facility (in years)		5 years
Maximum borrowing capacity		$ 2,300,000,000
Borrowings outstanding		$ 0		$ 0
Early termination penalties			$ 0
Foreign credit facilities \| Foreign subsidiaries facilities
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 291,500,000		291,500,000
Borrowings outstanding	$ 92,100,000		$ 92,100,000