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

Funds Held for Clients and Corporate Investments (Narrative) (Details)

v3.8.0.1

Funds Held for Clients and Corporate Investments (Narrative) (Details) $ in Millions	3 Months Ended
	Aug. 31, 2017 USD ($) security	Aug. 31, 2016 USD ($)	May 31, 2017 USD ($) security
Schedule of Available-for-sale Securities [Line Items]
Net unrealized gain on available-for-sale securities	$ 38.6		$ 32.0
Number of available-for-sale securities in an unrealized loss position \| security	149		216
Gross unrealized losses on available-for-sale securities	$ 3.6		$ 5.8
Realized losses on available-for-sale securities	$ 0.0	$ 0.0
Variable Rate Demand Notes [Member] \| Minimum [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities contractual maturities	20 years
Variable Rate Demand Notes [Member] \| Maximum [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities contractual maturities	30 years

- Definition

Available-for-sale Securities, Debt Maturities, Term

+ References

No definition available.

+ Details

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- Definition

The net change in the difference between the fair value and the carrying value of available for sale securities that are recognized in AOCI.

+ References

No definition available.

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- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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- Definition

This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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