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REGULATORY ASSETS (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Dec. 31, 2019
Regulatory Assets [Abstract] |  |
Contributions to postretirement benefit plan | $ 5,700 |
Cash received for bond issuance |  | $ 30,000,000
Amortization period of other regulatory expense [Abstract] |  |
Rate case studies | 5 years |
Goodwill | 50 years |
Deferred acquisition costs | 20 years |
Franchise costs | 80 years |
Regulatory assets net of amortization, comprise [Abstract] |  |
Regulatory assets, net | $ 6,785,000 | 6,891,000
Maximum [Member] |  |
Amortization period of other regulatory expense [Abstract] |  |
Debt related cost | 30 years |
Minimum [Member] |  |
Amortization period of other regulatory expense [Abstract] |  |
Debt related cost | 15 years |
Delaware [Member] |  |
Amortization period of other regulatory expense [Abstract] |  |
Regulatory rate proceedings | 2 years 6 months |
Maryland [Member] |  |
Amortization period of other regulatory expense [Abstract] |  |
Regulatory rate proceedings | 5 years |
Postretirement Benefit Obligation [Member] |  |
Regulatory assets net of amortization, comprise [Abstract] |  |
Regulatory assets, net | $ 51,000 | 51,000
Deferred Income Taxes [Member] |  |
Regulatory assets net of amortization, comprise [Abstract] |  |
Regulatory assets, net | 382,000 | 386,000
Debt Related Costs [Member] |  |
Regulatory assets net of amortization, comprise [Abstract] |  |
Regulatory assets, net | 25,000 | 27,000
Expense of Rate and Regulatory Proceedings [Member] |  |
Regulatory assets net of amortization, comprise [Abstract] |  |
Regulatory assets, net | 5,468,000 | 5,556,000
Goodwill [Member] |  |
Regulatory assets net of amortization, comprise [Abstract] |  |
Regulatory assets, net | 286,000 | 288,000
Deferred Acquisition and Franchise Costs [Member] |  |
Regulatory assets net of amortization, comprise [Abstract] |  |
Regulatory assets, net | $ 573,000 | $ 583,000

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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 Represents amortization period of debt related cost. + References No definition available. + Details
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- Definition Period over which regulatory noncurrent asset for deferred acquisition costs amortized. + References No definition available. + Details
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- Definition Period over which regulatory noncurrent asset for deferred franchise costs amortized. + 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 cash outflow for pension and other postretirement benefits. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585 + Details
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- Definition The cash inflow from amounts received from a long-term debt instrument secured by a first mortgage deed of trust, containing a pledge of real property. The lender has the highest claim on the property in case of default. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585 + Details
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- Definition Amortization period for the recovery of regulatory asset, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
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