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REGULATORY ASSETS - Regulatory Assets, Net of Amortization, Comprise (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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REGULATORY ASSETS [Abstract] |  |
Regulatory assets, net | $ 13,102 | $ 14,428
Deferred Contract Costs and Other [Member] |  |
REGULATORY ASSETS [Abstract] |  |
Regulatory assets, net | 165 | 271
Rate Case Studies [Member] |  |
REGULATORY ASSETS [Abstract] |  |
Regulatory assets, net | 114 | 141
Delaware Rate Proceedings [Member] |  |
REGULATORY ASSETS [Abstract] |  |
Regulatory assets, net | 342 | 474
Deferred Income Taxes [Member] |  |
REGULATORY ASSETS [Abstract] |  |
Regulatory assets, net | 408 | 423
Debt Related Costs [Member] |  |
REGULATORY ASSETS [Abstract] |  |
Regulatory assets, net | 3,705 | 3,969
Deferred Costs Affiliated Interest Agreement [Member] |  |
REGULATORY ASSETS [Abstract] |  |
Regulatory assets, net | 1,012 | 1,054
Goodwill [Member] |  |
REGULATORY ASSETS [Abstract] |  |
Regulatory assets, net | 245 | 251
Deferred Acquisition and Franchise Costs - Maryland [Member] |  |
REGULATORY ASSETS [Abstract] |  |
Regulatory assets, net | 361 | 389
Deferred Acquisition Costs - Delaware [Member] |  |
REGULATORY ASSETS [Abstract] |  |
Regulatory assets, net | 222 | 231
Deferred Acquisition Adjustments - Delaware [Member] |  |
REGULATORY ASSETS [Abstract] |  |
Regulatory assets, net | 3,306 | 3,359
Unrecovered Reserve for Depreciation [Member] |  |
REGULATORY ASSETS [Abstract] |  |
Regulatory assets, net | $ 3,222 | $ 3,866

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + 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 -Topic 980 -SubTopic 340 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478742/980-340-50-1 + Details
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