Derivatives and Hedging (Details) - Not Designated as Hedging Instrument - Foreign Exchange Contract - USD ($) $ in Millions	6 Months Ended
Nov. 30, 2019	Nov. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Derivative notional amount	$ 26.0	$ 30.0
Unrealized gain (loss)	$ (0.9)	$ (0.3)

Amount of net unrealized gain (loss) related to the change in fair value of foreign currency exchange rate derivatives designated as cash flow hedging instruments. Recorded in accumulated other comprehensive income to the extent that the cash flow hedge is determined to be effective.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959

Name:	us-gaap_UnrealizedGainLossOnForeignCurrencyDerivativesNetBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration