Paychex, Inc. Quarterly report pursuant to Section 13 or 15(d)

Short-term Financing (Credit Facility Amount Borrowed) (Details) - Revolving Credit Facility [Member] - USD ($) $ in Millions		3 Months Ended		6 Months Ended
	Dec. 01, 2019	Nov. 30, 2019	Nov. 30, 2018	Nov. 30, 2019	Nov. 30, 2018
JPM $1 Billion Credit Facility [Member] \| JP Morgan Chase Bank, N.A. [Member]
Line of Credit Facility [Line Items]
Number of days borrowed		10 days	4 days	16 days	10 days
Maximum amount borrowed		$ 694.0	$ 483.0	$ 694.0	$ 483.0
Weighted-average amount borrowed		$ 398.4	$ 389.8	$ 357.1	$ 285.7
Weighted-average interest rate		4.99%	5.12%	5.09%	5.06%
JPM $500 Million Credit Facility [Member] \| JP Morgan Chase Bank, N.A. [Member]
Line of Credit Facility [Line Items]
Number of days borrowed		14 days	3 days	24 days	7 days
Maximum amount borrowed		$ 400.0	$ 135.5	$ 450.0	$ 223.0
Weighted-average amount borrowed	$ 168.2	$ 305.0	$ 83.0	$ 342.8	$ 111.8
Weighted-average interest rate		3.15%	5.25%	3.21%	5.07%
PNC $150 Million Credit Facility [Member] \| PNC Bank, National Association [Member]
Line of Credit Facility [Line Items]
Number of days borrowed		91 days	91 days	179 days	179 days
Maximum amount borrowed		$ 56.7	$ 57.7	$ 56.7	$ 57.7
Weighted-average amount borrowed		$ 54.3	$ 57.3	$ 54.6	$ 56.6
Weighted-average interest rate		2.74%	2.68%	2.90%	2.61%