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

Service Revenue (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	May 31, 2021	May 31, 2020	May 31, 2019
Service Revenue [Line Items]
Notice of termination period	30 days
Revenue performance obligations timing	the Company defers revenue associated with these performance obligations, which exceed one year, and subsequently recognizes them as future services are provided, over approximately three years to four years
Impairment loss	$ 0.0	$ 0.0	$ 0.0
Minimum [Member]
Service Revenue [Line Items]
Revenue performance obligations timing, years	3 years
Maximum [Member]
Service Revenue [Line Items]
Revenue performance obligations timing, years	4 years