Summary of Significant Accounting Policies - Contract Assets and Liabilities and Remaining Performance Obligations (Details) - USD ($) $ in Millions	12 Months Ended
May 31, 2019	Jun. 01, 2018	May 31, 2018
Contract Assets and Liabilities
Contract assets - current	$ 59.2	$ 49.6
Contract assets - non-current	17.0	12.9	$ 39.0
Deferred revenue - current	(12.6)	(9.4)
Deferred revenue on long-term contracts	(83.8)	(34.7)	$ (35.8)
Net contract assets (liabilities)	(20.2)	$ 18.4
Change in contract assets - current	9.6
Change in contract assets - non-current	4.1
Change in contract liabilities - current	(3.2)
Change in contract liabilities - non-current	(49.1)
Change in net contract assets (liabilities)	(38.6)
Remaining Performance Obligations
Remaining performance obligation	$ 1,500.0
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-05-31
Remaining Performance Obligations
Percentage of remaining performance obligation expected to be recognized in the period	40.00%
Expected timing of satisfaction of remaining performance obligation	12 years
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-05-31
Remaining Performance Obligations
Percentage of remaining performance obligation expected to be recognized in the period	60.00%
Expected timing of satisfaction of remaining performance obligation	3 years

The amount of contract with customer asset after reducing liabilities.

No definition available.

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The noncurrent portion of deferred revenue on long-term contracts as of balance sheet date. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized, and is not expected to be recognized in the next twelve months. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

+ References

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Amount of increase (decrease) in right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time classified as current.

+ References

No definition available.

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Amount of increase (decrease) in contract with customer assets (liabilities) net.

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Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable classified as current.

+ References

No definition available.

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Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable classified as noncurrent.

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The percentage of remaining performance obligation expected to be recognized in the period.

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Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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