Name:	artna_ContractWithCustomerLiabilityRevenueRecognizedIncludingOpeningBalance
Namespace Prefix:	artna_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Minimum number of days services invoiced in advance beginning of every month for customer, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	artna_MinimumNumberOfDaysCustomersServicesInvoicedInAdvance
Namespace Prefix:	artna_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The minimum number of days due for accounts receivable after invoicing from regulated contract customers, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	artna_MinimumNumberOfDaysDueForAccountsReceivableFromRegulatedContractCustomers
Namespace Prefix:	artna_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The minimum number of days due for accounts receivable after invoicing from Service Line Protection Plans (SLP) customers, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	artna_MinimumNumberOfDaysDueForAccountsReceivableFromServiceLineProtectionPlanCustomer
Namespace Prefix:	artna_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Number of operation contracts paid in advance.

No definition available.

Name:	artna_NumberOfOperationContractsPaidInAdvance
Namespace Prefix:	artna_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Reserve or reduction to revenue from interim temporary rates.

No definition available.

Name:	artna_ReserveOrReductionToRevenue
Namespace Prefix:	artna_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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.

No definition available.

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

Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-SubTopic 10
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-13

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

Name:	us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis=us-gaap_RegulatedOperationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionStartDateAxis=2025-04-01
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis=us-gaap_UnregulatedOperationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis=artna_SLPPlanRevenueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis=artna_ContractServicesRevenueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: