Goodwill and Intangible Assets, Net of Accumulated Amortization (Change in Goodwill) (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2020	May 31, 2019
Goodwill and Intangible Assets, Net of Accumulated Amortization [Abstract]
Goodwill Balance, beginning of fiscal year	$ 1,782.6	$ 814.0
Changes during the period:
Goodwill acquired	4.1	972.1
Acquisition accounting adjustments	4.5	1.6
Currency translation adjustment	(0.1)	(5.1)
Goodwill Balance, end of fiscal year	$ 1,791.1	$ 1,782.6

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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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the 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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-Publisher FASB
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