XML 54 R43.htm IDEA: XBRL DOCUMENT
v3.20.2

INCOME TAXES (Details) | 9 Months Ended
--- | ---
Sep. 30, 2020 USD ($)
Income Taxes [Abstract] |
Income tax penalties and interest accrued for unrecognized tax position | $ 15,300
State Authorities [Member] |
Income Taxes [Abstract] |
Tax year open to examination | 2016 2017 2018 2019
Federal Authorities [Member] |
Income Taxes [Abstract] |
Tax year open to examination | 2016 2017 2018 2019

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

X
- Definition Tax year that remains open to examination under enacted tax laws, in CCYY format. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
Name: | us-gaap_OpenTaxYear
Namespace Prefix: | us-gaap_
Data Type: | us-types:gYearListItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of expense for penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32718-109319 + Details
Name: | us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=us-gaap_StateAndLocalJurisdictionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeTaxAuthorityAxis=us-gaap_InternalRevenueServiceIRSMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |