Acquisitions and Divestitures - Aggregate Purchase Price for Businesses Acquired (Details) - USD ($) $ in Thousands	May 31, 2016	May 31, 2015	May 31, 2014
Business Acquisition [Line Items]
Net goodwill recognized	$ 1,291,593	$ 1,195,612	$ 1,267,411
Series of Business Acquisitions
Business Acquisition [Line Items]
Fair value of tangible assets acquired	26,759	177
Net goodwill recognized	97,097	8,648
Total fair value of assets acquired	184,189	19,626
Fair value of liabilities assumed and incurred	27,610	4,131
Total cash paid for acquisitions	156,579	15,495
Series of Business Acquisitions \| Service Contracts
Business Acquisition [Line Items]
Fair value of intangible assets acquired	55,694	9,856
Series of Business Acquisitions \| Other Intangibles
Business Acquisition [Line Items]
Fair value of intangible assets acquired	$ 4,639	$ 945

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

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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

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- Definition

Amount of assets acquired at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 805
-SubTopic 10
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Amount of liabilities assumed at the acquisition date.

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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.

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