Debt - Schedule of Debt (Details) - USD ($) $ in Millions	Feb. 28, 2019	May 31, 2018	Feb. 28, 2018
Debt Instrument [Line Items]
Total Debt	$ 11.0	$ 7.9	$ 7.7
Line of Credit
Debt Instrument [Line Items]
Short-term debt		$ 7.9	$ 7.7
Weighted average interest rate (percentage)	4.30%	2.90%	3.70%
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term debt	$ 0.0	$ 0.0	$ 0.0

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Balance Type:	credit
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

+ References

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- Definition

Weighted average interest rate of short-term debt outstanding calculated at point in time.

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