Cover	9 Months Ended
	Jun. 30, 2021 shares
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2021
Document Transition Report	false
Entity File Number	001-04534
Entity Registrant Name	AIR PRODUCTS AND CHEMICALS, INC.
Entity Central Index Key	0000002969
Current Fiscal Year End Date	--09-30
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	23-1274455
Entity Address, Address Line One	7201 Hamilton Boulevard
Entity Address, City or Town	Allentown
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	18195-1501
City Area Code	610
Local Phone Number	481-4911
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding	221,364,660
Common Stock, par value $1.00 per share
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, par value $1.00 per share
Trading Symbol	APD
Security Exchange Name	NYSE
1.000% Euro Notes due 2025
Entity Information [Line Items]
Title of 12(b) Security	1.000% Euro Notes due 2025
Trading Symbol	APD25
Security Exchange Name	NYSE
0.500% Euro Notes due 2028
Entity Information [Line Items]
Title of 12(b) Security	0.500% Euro Notes due 2028
Trading Symbol	APD28
Security Exchange Name	NYSE
0.800% Euro Notes due 2032
Entity Information [Line Items]
Title of 12(b) Security	0.800% Euro Notes due 2032
Trading Symbol	APD32
Security Exchange Name	NYSE