Equity contributions or payments pertaining to guarantee obligation

No definition available.

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Namespace Prefix:	apd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percent Loan Guarateed

+ References

No definition available.

+ Details

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Namespace Prefix:	apd_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments.

+ References

No definition available.

+ Details

Name:	us-gaap_ContractualObligation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=115931803&loc=d3e12069-110248

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77896938&loc=d3e25336-109308

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

+ References

+ Details

Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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

Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_PerformanceGuaranteeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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- Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	apd_GuaranteeObligationsByNameAxis=apd_TrinidadFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	apd_GuaranteeObligationsByNameAxis=apd_UKAndIrelandHomecareBusinessMember
Namespace Prefix:
Data Type:	na
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Commitments and Contingencies (Guarantees and Other Narrative) (Details) £ in Millions, $ in Millions	Sep. 30, 2018 USD ($)	Sep. 30, 2018 GBP (£)	Sep. 30, 2017 USD ($)	Apr. 30, 2015
Guarantor Obligations [Line Items]
Obligation for future contribution to equity affiliate	$ 94.4		$ 94.4
Equity contributions or payments required	0.0
Unrecorded Unconditional Purchase Obligation [Line Items]
Unconditional purchase obligation	7,660.0
Purchase obligations in 2019	$ 851.0
Jazan Gas Projects Company
Guarantor Obligations [Line Items]
Ownership interest percentage	25.00%	25.00%
Obligation for future contribution to equity affiliate	$ 94.4		$ 94.4
Jazan Gas Projects Company \| Financial Guarantee
Guarantor Obligations [Line Items]
Percentage guaranteed share of loan				25.00%
Maximum potential payment under guarantees	100.0
Jazan Gas Projects Company \| Performance Guarantee
Guarantor Obligations [Line Items]
Maximum potential payment under guarantees	249.0
Helium Purchases
Unrecorded Unconditional Purchase Obligation [Line Items]
Unconditional purchase obligation	6,800.0
HyCO Feedstock Supply
Unrecorded Unconditional Purchase Obligation [Line Items]
Unconditional purchase obligation	210.0
Purchase Commitments for Plant and Equipment
Unrecorded Unconditional Purchase Obligation [Line Items]
Purchase obligations in 2019	$ 455.0
Trinidad Facility \| Performance Guarantee
Guarantor Obligations [Line Items]
Ownership interest percentage	50.00%	50.00%
Maximum potential payment under guarantees	$ 27.0
U.K. and Ireland Homecare Business \| Performance Guarantee
Guarantor Obligations [Line Items]
Maximum potential payment under guarantees	$ 25.0	£ 20