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REGULATORY ASSETS (Details) - USD ($) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2018 | Dec. 31, 2017
Regulatory Assets [Line Items] |  |
Artesian Water contributed to its postretirement benefit plan | $ 9,300 |
Amortization period of other regulatory expense [Abstract] |  |
Depreciation and salary studies | 5 years |
Goodwill | 50 years |
Deferred acquisition costs | 20 years |
Franchise costs | 80 years |
Summary of regulatory assets net of amortization, comprise [Abstract] |  |
Regulatory assets, net | $ 7,515,000 | $ 7,549,000
Maximum [Member] |  |
Amortization period of other regulatory expense [Abstract] |  |
Amortization period of debt related cost | 25 years |
Minimum [Member] |  |
Amortization period of other regulatory expense [Abstract] |  |
Amortization period of debt related cost | 15 years |
Maryland [Member] |  |
Amortization period of other regulatory expense [Abstract] |  |
Regulatory rate proceedings | 5 years |
Delaware [Member] |  |
Amortization period of other regulatory expense [Abstract] |  |
Regulatory rate proceedings | 2 years 6 months |
Postretirement Benefit Obligation [Member] |  |
Summary of regulatory assets net of amortization, comprise [Abstract] |  |
Regulatory assets, net | $ 149,000 | 149,000
Deferred Income Taxes (related to TCJA) [Member] |  |
Summary of regulatory assets net of amortization, comprise [Abstract] |  |
Regulatory assets, net | 412,000 | 416,000
Debt Related Costs [Member] |  |
Summary of regulatory assets net of amortization, comprise [Abstract] |  |
Regulatory assets, net | 68,000 | 70,000
Expense of Rate and Regulatory Proceedings [Member] |  |
Summary of regulatory assets net of amortization, comprise [Abstract] |  |
Regulatory assets, net | 5,948,000 | 5,965,000
Goodwill [Member] |  |
Summary of regulatory assets net of amortization, comprise [Abstract] |  |
Regulatory assets, net | 301,000 | 303,000
Deferred Acquisition and Franchise Costs [Member] |  |
Summary of regulatory assets net of amortization, comprise [Abstract] |  |
Regulatory assets, net | $ 637,000 | $ 646,000

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- Definition Period over which regulatory noncurrent assets for goodwill is amortized on a straight-line basis. + References No definition available. + Details
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- Definition Description of the amortization period for recovery of the individual regulatory noncurrent assets related to other expenses in a schedule of regulatory noncurrent assets. + References No definition available. + Details
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- Definition Amount of payment for pension and other postretirement benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585 + Details
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