Long-Term Financing (Narrative) (Details) - USD ($) $ in Millions	Nov. 30, 2019	May 31, 2019	Mar. 13, 2019
Aggregate principal amount	$ 800.0	$ 800.0
Senior Notes [Member]
Aggregate principal amount	800.0	800.0
Senior Notes [Member] | Company And Paychex Of New York [Member]
Aggregate principal amount			$ 800.0
Senior Notes, Series A [Member] | Senior Notes [Member]
Aggregate principal amount	$ 400.0	400.0
Principal payment dates	Mar. 13, 2026
Senior Notes, Series A [Member] | Senior Notes [Member] | Company And Paychex Of New York [Member]
Aggregate principal amount			$ 400.0
Principal payment dates			Mar. 13, 2026
Senior Notes, Series B [Member] | Senior Notes [Member]
Aggregate principal amount	$ 400.0	$ 400.0
Principal payment dates	Mar. 13, 2029
Senior Notes, Series B [Member] | Senior Notes [Member] | Company And Paychex Of New York [Member]
Aggregate principal amount			$ 400.0
Principal payment dates			Mar. 13, 2029