Name:	evtn_OperatingLeasePayments1
Namespace Prefix:	evtn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Represents information related to percentage of Increased base rent.

No definition available.

Name:	evtn_PercentageOfIncreasedBaseRent
Namespace Prefix:	evtn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

General description of claims, deemed to be reimbursable and included in accounts receivable, relating to the termination of long-term government contracts and programs. Includes claims associated with terminated war and defense contracts. If a reasonable estimate of a termination claim is undeterminable or impossible to make, disclosure is made to discuss the status and circumstances related to the undeterminable claim.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-SubTopic 310
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-Name Accounting Standards Codification
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Name:	us-gaap_ContractTerminationClaimsDescription
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

No definition available.

Name:	us-gaap_LeaseAndRentalExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Date which lease or group of leases is set to expire, in CCYY-MM-DD format.

No definition available.

Name:	us-gaap_LeaseExpirationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

Name:	us-gaap_LeasesAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Term of lessor's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Name:	us-gaap_LessorOperatingLeaseRenewalTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.