Commitments and Contingencies (Future Lease Obligations - Narrative) (Details) $ in Millions	Dec. 31, 2020 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Expected lease payments for operating leases that have not yet commenced	$ 250

Operating Lease, Expected Future Minimum Payments, Lease Not Yet Commenced

No definition available.

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