Equity contributions or payments pertaining to guarantee obligation

No definition available.

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

- Definition

Percent Loan Guarateed

+ References

No definition available.

+ Details

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

- Definition

Portion of the unrecorded unconditional purchase obligation maturing in the next two fiscal years following the latest fiscal year.

+ References

No definition available.

+ Details

Name:	apd_Unrecordedunconditionalpurchaseobligationbalanceonfirstandsecondanniversary
Namespace Prefix:	apd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

+ Details

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
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

Name:	us-gaap_GuaranteeObligationsLineItems
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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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

- Definition

Describe the approximate term of the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6851643&loc=d3e12069-110248

+ Details

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

- 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 440
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=73718637&loc=d3e25336-109308

+ Details

Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationBalanceOnFirstAnniversary
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

Name:	us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=apd_JazanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis=apd_HycoFeedstockSupplyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis=us-gaap_CapitalAdditionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis=apd_HeliumPurchasesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis=apd_JazanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- 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
Balance Type:
Period Type:

- Details

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

- Details

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

Commitments and Contingencies (Guarantees and Other) (Narrative) (Details) £ in Millions, $ in Millions	12 Months Ended
	Sep. 30, 2016 USD ($)	Sep. 30, 2016 GBP (£)	Sep. 30, 2015 USD ($)
Guarantor Obligations [Line Items]
Equity contributions or payments required	$ 0.0
Obligation for future contribution to equity affiliate	94.4		$ 67.5
Unrecorded Unconditional Purchase Obligation [Line Items]
2017	899.0
Unconditional purchase obligation	$ 5,288.0
Jazan [Member]
Guarantor Obligations [Line Items]
Percentage share of loan	25.00%	25.00%
Equity Method Investment, Ownership Percentage	25.00%	25.00%
Obligation for future contribution to equity affiliate	$ 94.4		$ 67.5
HYCO Feedstock Supply [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unconditional purchase obligation	330.0
Purchase commitments - additional plant and equipment [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
2017	310.0
Helium Purchases [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unconditional purchase obligation	4,000.0
Jazan [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
2017 and 2018	$ 500.0
Trinidad Facility [Member]
Guarantor Obligations [Line Items]
Equity Method Investment, Ownership Percentage	50.00%	50.00%
Maximum potential payment under guarantees	$ 29.0
Exposures under the guarantee completion year	by 2024
U.K. and Ireland Homecare Business [Member]
Guarantor Obligations [Line Items]
Maximum potential payment under guarantees	$ 25.0	£ 20
Exposures under the guarantee completion year	by 2020
Parent Guarantee [Member] \| Jazan [Member]
Guarantor Obligations [Line Items]
Maximum potential payment under guarantees	$ 100.0
Exposures under the guarantee completion year	until 2020
Bank Guarantee [Member] \| Jazan [Member]
Guarantor Obligations [Line Items]
Maximum potential payment under guarantees	$ 311.0