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- References

No definition available.

Name:	artna_DisclosureSubsequentEventsAbstract
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Number of business days of prior notice to be sent in the event it desires to repay any loan balance bearing interest at a fixed rate prior to the last day of the fixed rate period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	artna_NumberOfBusinessDaysOfPriorNotice
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Number of financial covenants in the events of default.

No definition available.

Name:	artna_NumberOfFinancialCovenants
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Period Type:	duration

Number of consecutive quarterly installments payable under the agreement.

No definition available.

Name:	artna_NumberOfQuarterlyInstallments
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Data Type:	xbrli:integerItemType
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Number of supplements in loan agreement.

No definition available.

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

The percentage of amount repaid, converted or not borrowed for the period such amount was scheduled to have been outstanding at such fixed rate.

No definition available.

Name:	artna_PercentageOfAmountRepaidConvertedOrNotBorrowed
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Percentage of annual yield repaid converted or not borrowed for the period such amount was scheduled to have been outstanding at such fixed rate.

No definition available.

Name:	artna_PercentageOfAnnualYieldOfRepaid
Namespace Prefix:	artna_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Percentage of long-term financing on the cost of facility.

No definition available.

Name:	artna_PercentageOfLongTermFinancingCost
Namespace Prefix:	artna_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The ratio of total debt to capitalization to determine the financial leverage.

No definition available.

Name:	artna_RatioOfTotalDebtToCapitalizationRatio
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Data Type:	num:percentItemType
Balance Type:	na
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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 470
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-Section 50
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Period Type:	instant

Description of the frequency of periodic payments (monthly, quarterly, annual).

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Contractual interest rate for funds borrowed, under the debt agreement.

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

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