Leases - Supplemental cash flow information (Details) $ in Millions	3 Months Ended	9 Months Ended
Feb. 29, 2020 USD ($)	Feb. 29, 2020 USD ($)
Leases
Weighted-average remaining lease term (years)	8 years 8 months 12 days	8 years 8 months 12 days
Weighted-average discount rate	3.60%	3.60%
Cash paid for amounts included in the measurement of lease liabilities	$ 2.4	$ 10.0
Operating lease liabilities arising from obtaining ROU assets	$ 0.1	$ 13.2

No definition available.

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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+ Details

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- Definition

Weighted average discount rate for operating lease calculated at point in time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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- Definition

Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

+ References

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+ Details

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