Variable Interest Entity, Obligation To Absorb Risk, Percentage Of Equity

No definition available.

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Namespace Prefix:	aqua_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- 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.

+ Details

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

- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=123419778&loc=SL6759159-111685

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_BusinessAcquisitionAxis=aqua_FrontierMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=aqua_MinorityOwnersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ConsolidatedEntitiesAxis=aqua_TreatedWaterOutsourcingMember
Namespace Prefix:
Data Type:	na
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Period Type:

Variable Interest Entities (Narrative) (Details)	12 Months Ended
Variable Interest Entities (Narrative) (Details)	Sep. 30, 2022	Apr. 01, 2022	Apr. 30, 2021	Feb. 28, 2021	Oct. 01, 2019
Variable Interest Entity [Line Items]
Variable interest entity, obligation to absorb risk, percentage of equity	100.00%
Frontier
Variable Interest Entity [Line Items]
Business acquisition, percentage of voting interests acquired		32.00%	8.00%		60.00%
Frontier \| Minority Owners
Variable Interest Entity [Line Items]
Ownership interest remaining				10.00%	40.00%
Treated Water Outsourcing
Variable Interest Entity [Line Items]
Variable interest entity, ownership percentage	50.00%