Additional percentage employer matches of the employee's percentage contribution matched.

No definition available.

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Represents gross pay rate of matched employee contributions.

No definition available.

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Namespace Prefix:	artna_
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Balance Type:	na
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Amount of administrative expense incurred by defined contribution plan.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

No definition available.

Name:	us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Percentage employer matches of the employee's percentage contribution matched.

No definition available.

Name:	us-gaap_DefinedContributionPlanEmployerMatchingContributionPercentOfMatch
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

No definition available.

Name:	us-gaap_DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

No definition available.

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Namespace Prefix:
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Balance Type:
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EMPLOYEE BENEFIT PLANS (Details) - 401(k) Plan [Member] - Artesian Resources [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Retirement Benefits, Description [Abstract]
Percentages of contribution of eligible salaries and wages by Artesian Resources	2.00%
Percentages of matched employee contributions	6.00%
Gross pay rate of matched employee contributions	50.00%
Percentages of additional contribution the Company can make from eligible salaries and wages	3.00%
Entity contributions and administrative fees	$ 1.1	$ 1.1	$ 1.1
Minimum [Member]
Retirement Benefits, Description [Abstract]
Percentages of additional contribution of eligible salaries and wages by Artesian Resources	2.00%
Maximum [Member]
Retirement Benefits, Description [Abstract]
Percentages of additional contribution of eligible salaries and wages by Artesian Resources	6.00%