Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=109250915&loc=d3e13433-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Stated rate on an interest rate forward or futures contract.

+ References

No definition available.

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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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Derivative Instrument and Hedging Activity (Details) - Designated as Hedging Instrument - Interest Rate Swap - USD ($)	May 31, 2021	May 31, 2020	May 31, 2019	Sep. 30, 2018	May 31, 2018	Dec. 31, 2017	May 31, 2017
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative rate							1.81%
Derivative, notional amount					$ 65,000,000.0		$ 65,000,000.0
Interest rate swap derivative instrument				$ 1,600,000		$ 500,000
Scenario, Forecast
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	$ 25,000,000.0	$ 25,000,000.0	$ 65,000,000.0