Name:	artna_MinimumNumberOfDaysCustomersServicesInvoicedInAdvance
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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

The total amount of revenue recognized for the period from rental income and other revenue.

No definition available.

Name:	artna_OtherOperatingRevenueNotInScopeOfASC606
Namespace Prefix:	artna_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

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- References

No definition available.

Name:	us-gaap_RevenueFromContractWithCustomerAbstract
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Balance Type:	na
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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 32
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Section 50
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130545-203045

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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Name:	us-gaap_ProductOrServiceAxis=artna_ConsumptionChargesMember
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Name:	us-gaap_ProductOrServiceAxis=artna_FixedFeesMember
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Data Type:	na
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Name:	us-gaap_ProductOrServiceAxis=artna_ServiceChargesMember
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Name:	us-gaap_ProductOrServiceAxis=artna_DistributionSystemImprovementChargeMember
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Name:	us-gaap_ProductOrServiceAxis=artna_RevenueReservedForRefundTCJAImpactMember
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Name:	us-gaap_PublicUtilityRegulatedOrUnregulatedStatusAxis=us-gaap_UnregulatedOperationMember
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Name:	us-gaap_ProductOrServiceAxis=artna_ServiceLineProtectionPlansMember
Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_ProductOrServiceAxis=artna_ContractOperationsMember
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Data Type:	na
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