Annual report pursuant to Section 13 and 15(d)

Document and Entity Information

Document and Entity Information - USD ($)
12 Months Ended
May 31, 2021
Jun. 30, 2021
Nov. 30, 2020
Document and Entity Information [Abstract]      
Document Type 10-K    
Document Annual Report true    
Document Fiscal Period Focus FY    
Current Fiscal Year End Date --05-31    
Document Fiscal Year Focus 2021    
Document Period End Date May 31, 2021    
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 Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
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    
ICFR Auditor Attestation Flag true    
Entity Shell Company false    
Entity Public Float     $ 29,976,304,817
Entity Common Stock, Shares Outstanding   359,830,185  
Documents Incorporated by Reference Portions of the registrant’s definitive proxy statement to be issued in connection with its Annual Meeting of Stockholders to be held on or about October 14, 2021, to the extent not set forth herein, are incorporated by reference into Part III, Items 10 through 14, inclusive.    
Amendment Flag false    
Entity Central Index Key 0000723531