Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
May 31, 2019	May 31, 2018
Fair Value Disclosures [Abstract]
Settlements of contingent consideration obligations	$ 5.2	$ 3.9
Increase in accrual related to fair value adjustments	3.0	0.5
Increase in accrual related to new acquisitions	$ 5.8	$ 3.4

Increase (decrease) in business combination contingent consideration liability.

No definition available.

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- Definition

Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e7008-128479

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- References

No definition available.

+ Details

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- Definition

Cash outflow representing an adjustment to the purchase price of a previous acquisition.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585

+ Details

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