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REGULATORY PROCEEDINGS (Details) (USD $)	12 Months Ended	0 Months Ended				1 Months Ended	12 Months Ended
	Dec. 31, 2014	Nov. 30, 2014	Nov. 13, 2014	May 31, 2013	Nov. 30, 2012	Nov. 30, 2013	Dec. 31, 2013	Jun. 10, 2014	Apr. 11, 2014	Jan. 18, 2013
Rate Proceedings [Abstract]
Reclassification of accumulated depreciation to deferred credits	$ 1,200,000artna_ReclassificationOfAccumulatedDepreciationToDeferredCredits
Delaware [Member]
Rate Proceedings [Abstract]
Maximum temporary annual rate increase subject to 15% gross water sales limitation	2,500,000artna_MaximumAmountOfTemporaryRateIncreasePerRateSettingProcess / us-gaap_StatementGeographicalAxis = stpr_DE
Percentage of gross water sales maximum temporary annual rate increase subject to $2.5 million limitation (in hundredths)	15.00%artna_PercentageOfGrossWaterSalesMaximumTemporaryAnnualRateIncreaseSubjectToCeilingLimitation / us-gaap_StatementGeographicalAxis = stpr_DE
Period to complete rate case by law	7 months
Percentage of rate relief allowed should a rate case not complete, maximum (in hundredths)	15.00%artna_MaximumPercentageOfReliefIfRateCasePeriodConditionNotFulfill / us-gaap_StatementGeographicalAxis = stpr_DE
Other Proceedings [Abstract]
Distribution System Improvement Charge rate increase applied between base rate filings, maximum (in hundredths)	7.50%artna_DistributionSystemImprovementChargeRateCeilingPercentage / us-gaap_StatementGeographicalAxis = stpr_DE
Distribution System Improvement Charge rate increase maximum within a 12-month period (in hundredths)	5.00%artna_DistributionSystemImprovementChargeRateConditionalIncrease / us-gaap_StatementGeographicalAxis = stpr_DE
Artesian Water [Member]
Rate Proceedings [Abstract]
Percentage of revenue increase requested for new rates (in hundredths)									15.90%artna_PercentageOfRevenueIncreaseRequestedForNewRates / dei_LegalEntityAxis = artna_ArtesianWaterMember
Increase in annual revenue expected from rate increase application approval									10,000,000artna_IncreaseInAnnualRevenueExpectedFromApplicationFiledForIncreaseFromRegulatoryAgency / dei_LegalEntityAxis = artna_ArtesianWaterMember
Percentage increase in annual operating revenue due to temp rate increase in effect								3.98%artna_PercentageIncreaseInAnnualOperatingRevenueDueToTempRateIncreaseInEffect / dei_LegalEntityAxis = artna_ArtesianWaterMember
Annualized operating revenue increase due to temp rate increase in effect								2,500,000artna_AnnualizedOperatingRevenueIncreaseDueToTempRateIncreaseInEffect / dei_LegalEntityAxis = artna_ArtesianWaterMember
Other Proceedings [Abstract]
Increase in annual revenue expected from rate increase application approval									10,000,000artna_IncreaseInAnnualRevenueExpectedFromApplicationFiledForIncreaseFromRegulatoryAgency / dei_LegalEntityAxis = artna_ArtesianWaterMember
Percentage of Distribution System Improvement Charges annual rate increase application filed by company to regulatory (in hundredths)	3.32%artna_PercentageOfDistributionSystemImprovementChargeRateIncreaseApplicationFiledByCompanyToRegulatory / dei_LegalEntityAxis = artna_ArtesianWaterMember	0.34%artna_PercentageOfDistributionSystemImprovementChargeRateIncreaseApplicationFiledByCompanyToRegulatory / dei_LegalEntityAxis = artna_ArtesianWaterMember	7.17%artna_PercentageOfDistributionSystemImprovementChargeRateIncreaseApplicationFiledByCompanyToRegulatory / dei_LegalEntityAxis = artna_ArtesianWaterMember	0.50%artna_PercentageOfDistributionSystemImprovementChargeRateIncreaseApplicationFiledByCompanyToRegulatory / dei_LegalEntityAxis = artna_ArtesianWaterMember	1.45%artna_PercentageOfDistributionSystemImprovementChargeRateIncreaseApplicationFiledByCompanyToRegulatory / dei_LegalEntityAxis = artna_ArtesianWaterMember	1.23%artna_PercentageOfDistributionSystemImprovementChargeRateIncreaseApplicationFiledByCompanyToRegulatory / dei_LegalEntityAxis = artna_ArtesianWaterMember
Increase Amount Based On Eligible Plant Improvements Since Last Rate Increase		1,300,000artna_IncreaseAmountBasedOnEligiblePlantImprovementsSinceLastRateIncrease / dei_LegalEntityAxis = artna_ArtesianWaterMember	4,500,000artna_IncreaseAmountBasedOnEligiblePlantImprovementsSinceLastRateIncrease / dei_LegalEntityAxis = artna_ArtesianWaterMember	2,000,000artna_IncreaseAmountBasedOnEligiblePlantImprovementsSinceLastRateIncrease / dei_LegalEntityAxis = artna_ArtesianWaterMember	5,600,000artna_IncreaseAmountBasedOnEligiblePlantImprovementsSinceLastRateIncrease / dei_LegalEntityAxis = artna_ArtesianWaterMember	4,900,000artna_IncreaseAmountBasedOnEligiblePlantImprovementsSinceLastRateIncrease / dei_LegalEntityAxis = artna_ArtesianWaterMember
Revenue earned in DSIC rate increases	800,000artna_RevenueEarnedInDistributionSystemImprovementCharge / dei_LegalEntityAxis = artna_ArtesianWaterMember						1,100,000artna_RevenueEarnedInDistributionSystemImprovementCharge / dei_LegalEntityAxis = artna_ArtesianWaterMember
Artesian Wastewater [Member]
Rate Proceedings [Abstract]
Percentage of revenue increase requested for new rates (in hundredths)										34.80%artna_PercentageOfRevenueIncreaseRequestedForNewRates / dei_LegalEntityAxis = artna_ArtesianWastewaterMember
Amount of annual revenue increase in a filed request to implement new rates										343,000artna_AmountOfAnnualRevenueIncreaseInFiledRequestToImplementNewRates / dei_LegalEntityAxis = artna_ArtesianWastewaterMember
Increase in annual revenue expected from rate increase application approval										174,000artna_IncreaseInAnnualRevenueExpectedFromApplicationFiledForIncreaseFromRegulatoryAgency / dei_LegalEntityAxis = artna_ArtesianWastewaterMember
Return on Equity (in hundredths)	10.00%artna_ReturnOnEquityPercentage / dei_LegalEntityAxis = artna_ArtesianWastewaterMember
Other Proceedings [Abstract]
Increase in annual revenue expected from rate increase application approval										$ 174,000artna_IncreaseInAnnualRevenueExpectedFromApplicationFiledForIncreaseFromRegulatoryAgency / dei_LegalEntityAxis = artna_ArtesianWastewaterMember

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- Definition

For a filing request with a regulatory agency to implement new rates, the expected annual revenue increase upon approval of new rates requested.

+ References

No definition available.

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Annualized operating revenue increase due to temp rate increase in effect

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- Definition

Ceiling percentage of Distribution System Improvement Charge rate subject to amount billed to customers.

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No definition available.

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- Definition

Conditional percentage maximum for increasing Distribution System Improvement Charge rate within a 12-month period.

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No definition available.

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- Definition

Increase amount based on eligible plant improvements since the last rate increase.

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No definition available.

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Increase in annual revenue expected from rate increase request with regulatory agency.

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- Definition

For a first temporary increase in revenue basis, maximum temporary annual rate charge increase subject to specific gross water sales limitation.

+ References

No definition available.

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- Definition

Maximum percentage of relief that utility may put into effect if condition for rate case period completion not fulfill by law.

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No definition available.

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Percentage increase in annual op rev due to temp rate increase in effect

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Percentage of Distribution System Improvement Charge rate increase application filed by company to regulatory.

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For a first temporary annual rate increase in revenue basis, maximum percentage of gross water sales increase allowed subject to specific dollar amount limitation.

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For a filing request with a regulatory agency to implement new rates, the percentage increase in annual revenue expected upon rate approval.

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No definition available.

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Period within which rate change case is to complete, by law, after which, entire requested rate relief may go into effect.

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Reclassification of accumulated depreciation to deferred credits and other liabilities on consolidated balance sheet.

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The amount of net income returned as a percentage of shareholders' equity. Return on equity is expressed as a percentage and calculated as: Return on Equity = Net Income/Shareholders' Equity.

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Revenue earned due to Distribution System Improvement Charge rate increase.

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