Acquisitions - Aggregate Purchase Price and Fair Value Allocations (Details) - USD ($) $ in Thousands	May 31, 2019	May 31, 2018	May 31, 2017
Business Acquisition [Line Items]
Net goodwill recognized	$ 2,842,441	$ 2,846,888	$ 2,782,335
Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Fair value of tangible assets acquired	840	421
Net goodwill recognized	6,637	12,094
Total fair value of assets acquired	16,576	22,678
Fair value of liabilities assumed	6,763	3,332
Total cash paid for acquisitions, net of cash acquired	9,813	19,346
Series of Individually Immaterial Business Acquisitions \| Service contracts
Business Acquisition [Line Items]
Fair value of intangible assets acquired	8,064	9,271
Series of Individually Immaterial Business Acquisitions \| Other intangibles
Business Acquisition [Line Items]
Fair value of intangible assets acquired	$ 1,035	$ 892

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets, Including Goodwill

No definition available.

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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.

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
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- Definition

Amount of liabilities assumed at the acquisition date.

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-Publisher FASB
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- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

+ References

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- Definition

Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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