XML 83 R61.htm IDEA: XBRL DOCUMENT v3.25.4

Regulatory Matters - Pending Infrastructure Surcharge Filings Additional Information (Details) - USD ($) $ in Millions	Jan. 20, 2026	Sep. 03, 2025	Jun. 30, 2025
Indiana | Subsequent Event
Public Utilities, General Disclosures [Line Items]
Infrastructure surcharge, annualized incremental revenues, requested amount	$ 15
Missouri
Public Utilities, General Disclosures [Line Items]
Infrastructure surcharge, annualized incremental revenues, requested amount		$ 13
West Virginia
Public Utilities, General Disclosures [Line Items]
Infrastructure surcharge, annualized incremental revenues, requested amount			$ 3

X

- Definition

Public Utilities, Infrastructure Surcharge, Annualized Incremental Revenues, Requested Amount

+ References

No definition available.

+ Details

Name:	awk_PublicUtilitiesInfrastructureSurchargeAnnualizedIncrementalRevenuesRequestedAmount
Namespace Prefix:	awk_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

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

X

- Details

Name:	srt_StatementGeographicalAxis=stpr_IN
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_StatementGeographicalAxis=stpr_MO
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	srt_StatementGeographicalAxis=stpr_WV
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: