Paychex, Inc. Annual report pursuant to Section 13 and 15(d)

Short-term Financing (Lines of Credit Facility Amount Available) (Details) - Line of Credit [Member] $ in Millions	12 Months Ended
	May 31, 2017 USD ($)
JP Morgan Chase Bank, N.A. [Member]
Line of Credit Facility [Line Items]
Amount available	$ 350
Expiration date	Feb. 28, 2018
Bank of America, N.A. [Member]
Line of Credit Facility [Line Items]
Amount available	$ 250
Expiration date	Feb. 28, 2018
PNC Bank, National Association [Member]
Line of Credit Facility [Line Items]
Amount available	$ 150
Expiration date	Feb. 28, 2018
Wells Fargo Bank, National Association [Member]
Line of Credit Facility [Line Items]
Amount available	$ 150
Expiration date	Feb. 28, 2018