Commitments and Contingencies (Future Lease Obligations - Narrative) (Details) $ in Millions	Mar. 31, 2021 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Expected lease payments for operating leases that have not yet commenced	$ 250

Total estimated lease payments for operating leases that have not yet commenced.

No definition available.

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