Revenue Recognition - Contract Assets and Liabilities (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Nov. 30, 2018	Nov. 30, 2017	Nov. 30, 2018	Nov. 30, 2017	Jun. 01, 2018
Contract Assets and Liabilities
Contract assets-current	$ 63.0		$ 63.0		$ 49.6
Contract assets - non-current	21.3		21.3		12.9
Contract liabilities - current	(9.3)		(9.3)		(9.4)
Contract liabilities - non-current	(68.3)		(68.3)		(33.0)
Net contract assets	6.7		6.7		$ 20.1
Change in contract assets - current			13.4
Change in contract assets - Noncurrent			8.4
Change in contract liabilities - current			0.1
Change in contract liabilities - non-current			(35.3)
Change in net contract assets			(13.4)
Revenue recognized	76.4		156.5
Provision for doubtful accounts	12.4	$ 0.1	13.0	$ 0.3
Impairment of non-current contract assets	7.6
Allowance for doubtful accounts	3.3		3.3
Other liabilities	$ 1.5		$ 1.5

The amount of contract with customer asset after reducing liabilities.

No definition available.

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- Definition

Amount of write-down of non-current contract assets.

+ References

No definition available.

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- Definition

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.

+ 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 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.

+ References

No definition available.

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- Definition

For an unclassified balance sheet, a valuation allowance for receivables due a company that are expected to be uncollectible.

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- Definition

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.

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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 obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Amount of liabilities classified as other.

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Amount of expense related to write-down of receivables to the amount expected to be collected. Includes, but is not limited to, accounts receivable and notes receivable.

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