The amount of contract with customer asset after reducing liabilities.

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Forward loss reserves and other related charges.

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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.

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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.

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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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Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration from customer has been received or is due, other.

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No definition available.

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- Definition

Amount of expense (reversal of expense) for expected credit loss on right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

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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.

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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 deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable, classified as current.

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Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable, classified as noncurrent.

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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.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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

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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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Percentage of remaining performance obligation to total remaining performance obligation not recognized as revenue.

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Revenue Recognition - Contract Assets and Liabilities and Remaining Performance Obligations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Feb. 29, 2020	Feb. 28, 2019	Feb. 29, 2020	Feb. 28, 2019	May 31, 2019
Contract Assets and Liabilities
Contract assets - current	$ 64.7		$ 64.7		$ 59.2
Contract assets - non-current	25.1		25.1		17.0
Deferred revenue - current	(13.4)		(13.4)		(12.6)
Deferred revenue on long-term contracts	(101.3)		(101.3)		(83.8)
Net contract liabilities	(24.9)		(24.9)		$ (20.2)
Change in contract assets - current			5.5
Change in contract assets - non-current			8.1
Change in contract liabilities - current			(0.8)
Change in contract liabilities - non-current			(17.5)
Net contract liabilities			(4.7)
Contracts charge	24.7
Contract assets and revenue	9.8
Other related charges	14.9
Change in Contract with Customer, Liability
Deferred revenue at beginning of period	(133.8)	$ (77.6)	(96.4)	$ (44.1)
Revenue deferred	(102.1)	(109.3)	(342.4)	(303.3)
Revenue recognized	121.7	91.3	326.0	247.8
Other	(0.5)	(1.7)	(1.9)	2.3
Deferred revenue at end of period	(114.7)	$ (97.3)	(114.7)	$ (97.3)
Remaining Performance Obligations
Remaining performance obligation	$ 1,100.0		$ 1,100.0
Revenue, Remaining Performance Obligation, Percentage	40.00%		40.00%
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-05-31
Remaining Performance Obligations
Expected timing of satisfaction of remaining performance obligation	12 months		12 months