XML 62 R48.htm IDEA: XBRL DOCUMENT
v3.3.1.900

REGULATORY PROCEEDINGS (Details) - USD ($) |  |  |  |  |  |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Nov. 24, 2015 | Aug. 18, 2015 | May. 31, 2015 | Nov. 30, 2014 | Nov. 13, 2014 | Dec. 17, 2013 | Jan. 18, 2013 | Dec. 31, 2015 | Dec. 31, 2014 | Jun. 10, 2014 | Apr. 11, 2014
Rate Proceedings [Abstract] |  |  |  |  |  |  |  |  |  |  |
Return on Equity |  |  |  |  |  |  | 10.00% |  |  |  |
Reclassification of accumulated depreciation to deferred credits |  |  |  |  |  |  |  | $ 1,200,000 |  |  |
Delaware [Member] |  |  |  |  |  |  |  |  |  |  |
Rate Proceedings [Abstract] |  |  |  |  |  |  |  |  |  |  |
Maximum temporary annual rate increase subject to 15% gross water sales limitation |  |  |  |  |  |  |  | $ 2,500,000 |  |  |
Percentage of gross water sales maximum temporary annual rate increase subject to $2.5 million limitation |  |  |  |  |  |  |  | 15.00% |  |  |
Period to complete rate case by law |  |  |  |  |  |  |  | 7 months |  |  |
Percentage of rate relief allowed should a rate case not complete, maximum |  |  |  |  |  |  |  | 15.00% |  |  |
Other Proceedings [Abstract] |  |  |  |  |  |  |  |  |  |  |
Distribution System Improvement Charge rate increase applied between base rate filings, maximum |  |  |  |  |  |  |  | 7.50% |  |  |
Distribution System Improvement Charge rate increase maximum within a 12-month period |  |  |  |  |  |  |  | 5.00% |  |  |
Artesian Water [Member] |  |  |  |  |  |  |  |  |  |  |
Rate Proceedings [Abstract] |  |  |  |  |  |  |  |  |  |  |
Percentage of revenue increase requested for new rates |  |  |  |  |  |  |  |  |  |  | 15.90%
Incremental Increase to Customers |  |  |  |  |  |  |  |  |  |  | 12.58%
Increase in annual revenue expected from rate increase application approval |  |  |  |  |  |  |  |  |  |  | $ 10,000,000
Percentage increase in annual operating revenue due to temp rate increase in effect |  |  |  |  |  |  |  |  |  | 3.98% |
Annualized operating revenue increase due to temp rate increase in effect |  |  |  |  |  |  |  |  |  | $ 2,500,000 |
Permanent rate increase in revenue |  | $ 6,000,000 |  |  |  |  |  |  |  |  |
Percentage of Permanent Rate Increases on an annualized basis (in hundredths) |  | 9.50% |  |  |  |  |  |  |  |  |
An incremental increase to customers above the DSIC rate previously in effect |  | 6.20% |  |  |  |  |  |  |  |  |
Other Proceedings [Abstract] |  |  |  |  |  |  |  |  |  |  |
Increase in annual revenue expected from rate increase application approval |  |  |  |  |  |  |  |  |  |  | $ 10,000,000
Percentage of Distribution System Improvement Charges annual rate increase application filed by company to regulatory | 1.57% |  | 1.15% | 0.34% | 7.17% | 3.32% |  | 3.32% |  |  |
Increase Amount Based On Eligible Plant Improvements Since Last Rate Increase | $ 7,000,000 |  | $ 4,600,000 | $ 1,300,000 | $ 4,500,000 | $ 12,900,000 |  |  |  |  |
Revenue earned in DSIC rate increases |  |  |  |  |  |  |  | $ 520,000.0 | $ 789,000.0 |  |
Artesian Wastewater [Member] |  |  |  |  |  |  |  |  |  |  |
Rate Proceedings [Abstract] |  |  |  |  |  |  |  |  |  |  |
Percentage of revenue increase requested for new rates |  |  |  |  |  |  | 34.80% |  |  |  |
Amount of annual revenue increase in a filed request to implement new rates |  |  |  |  |  |  | $ 343,000 |  |  |  |
Increase in annual revenue expected from rate increase application approval |  |  |  |  |  |  | 174,000 |  |  |  |
Other Proceedings [Abstract] |  |  |  |  |  |  |  |  |  |  |
Increase in annual revenue expected from rate increase application approval |  |  |  |  |  |  | $ 174,000 |  |  |  |

X
- 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. + Details
Name: | artna_AmountOfAnnualRevenueIncreaseInFiledRequestToImplementNewRates
Namespace Prefix: | artna_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Annualized operating revenue increase due to temp rate increase in effect. + References No definition available. + Details
Name: | artna_AnnualizedOperatingRevenueIncreaseDueToTempRateIncreaseInEffect
Namespace Prefix: | artna_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | instant

X
- Definition Ceiling percentage of Distribution System Improvement Charge rate subject to amount billed to customers. + References No definition available. + Details
Name: | artna_DistributionSystemImprovementChargeRateCeilingPercentage
Namespace Prefix: | artna_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Conditional percentage maximum for increasing Distribution System Improvement Charge rate within a 12-month period. + References No definition available. + Details
Name: | artna_DistributionSystemImprovementChargeRateConditionalIncrease
Namespace Prefix: | artna_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Increase amount based on eligible plant improvements since the last rate increase. + References No definition available. + Details
Name: | artna_IncreaseAmountBasedOnEligiblePlantImprovementsSinceLastRateIncrease
Namespace Prefix: | artna_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Increase in annual revenue expected from rate increase request with regulatory agency. + References No definition available. + Details
Name: | artna_IncreaseInAnnualRevenueExpectedFromApplicationFiledForIncreaseFromRegulatoryAgency
Namespace Prefix: | artna_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Incremental increase to customers. + References No definition available. + Details
Name: | artna_IncrementalIncreaseToCustomers
Namespace Prefix: | artna_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- 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. + Details
Name: | artna_MaximumAmountOfTemporaryRateIncreasePerRateSettingProcess
Namespace Prefix: | artna_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Maximum percentage of relief that utility may put into effect if condition for rate case period completion not fulfill by law. + References No definition available. + Details
Name: | artna_MaximumPercentageOfReliefIfRateCasePeriodConditionNotFulfill
Namespace Prefix: | artna_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | artna_OtherProceedingsAbstract
Namespace Prefix: | artna_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage increase in annual op rev due to temp rate increase in effect. + References No definition available. + Details
Name: | artna_PercentageIncreaseInAnnualOperatingRevenueDueToTempRateIncreaseInEffect
Namespace Prefix: | artna_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Percentage of Distribution System Improvement Charge rate increase application filed by company to regulatory. + References No definition available. + Details
Name: | artna_PercentageOfDistributionSystemImprovementChargeRateIncreaseApplicationFiledByCompanyToRegulatory
Namespace Prefix: | artna_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition For a first temporary annual rate increase in revenue basis, maximum percentage of gross water sales increase allowed subject to specific dollar amount limitation. + References No definition available. + Details
Name: | artna_PercentageOfGrossWaterSalesMaximumTemporaryAnnualRateIncreaseSubjectToCeilingLimitation
Namespace Prefix: | artna_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition For a filing request with a regulatory agency to implement new rates, the percentage increase in annual revenue expected upon rate approval. + References No definition available. + Details
Name: | artna_PercentageOfRevenueIncreaseRequestedForNewRates
Namespace Prefix: | artna_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Period within which rate change case is to complete, by law, after which, entire requested rate relief may go into effect. + References No definition available. + Details
Name: | artna_PeriodToCompleteRateChangeApplicationCase
Namespace Prefix: | artna_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | artna_RateProceedingsAbstract
Namespace Prefix: | artna_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Reclassification of accumulated depreciation to deferred credits and other liabilities on consolidated balance sheet. + References No definition available. + Details
Name: | artna_ReclassificationOfAccumulatedDepreciationToDeferredCredits
Namespace Prefix: | artna_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition 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. + References No definition available. + Details
Name: | artna_ReturnOnEquityPercentage
Namespace Prefix: | artna_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Revenue earned due to Distribution System Improvement Charge rate increase. + References No definition available. + Details
Name: | artna_RevenueEarnedInDistributionSystemImprovementCharge
Namespace Prefix: | artna_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition An incremental increase to customers above the DSIC rate previously in effect. + References No definition available. + Details
Name: | artna_artna_incrementalincreaseforcustomersaboveDSICratepreviouslyineffect
Namespace Prefix: | artna_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of public utility's approved rate increase (decrease) by regulatory agency. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesApprovedRateIncreaseDecreaseAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Percentage of public utility's approved rate increase (decrease) by regulatory agency. + References No definition available. + Details
Name: | us-gaap_PublicUtilitiesApprovedRateIncreaseDecreasePercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StatementGeographicalAxis=stpr_DE
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=artna_ArtesianWaterMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=artna_ArtesianWastewaterMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |