Quarterly report pursuant to Section 13 or 15(d)

Document and Entity Information

Document and Entity Information - shares
3 Months Ended
Aug. 31, 2020
Sep. 30, 2020
Document and Entity Information [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Aug. 31, 2020  
Document Transition Report false  
Entity File Number 0-11330  
Entity Registrant Name Paychex, Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 16-1124166  
Entity Address, Address Line One 911 Panorama Trail South  
Entity Address, City or Town Rochester  
Entity Address, State or Province NY  
Entity Address, Postal Zip Code 14625-2396  
City Area Code 585  
Local Phone Number 385-6666  
Title of 12(b) Security Common Stock, $0.01 par value  
Trading Symbol PAYX  
Security Exchange Name NASDAQ  
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   359,500,317
Amendment Flag false  
Document Fiscal Period Focus Q1  
Current Fiscal Year End Date --05-31  
Document Fiscal Year Focus 2021  
Entity Central Index Key 0000723531