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INCOME TAXES (Details) - USD ($) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2022 | Dec. 31, 2021 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2018 | Dec. 31, 2017 | Jan. 31, 2019
Income Taxes [Abstract] |  |  |  |  |  |  |  |
Federal corporate tax rate |  |  | 21.00% | 21.00% | 21.00% |  | 34.00% |
Decrease in the net deferred income tax liability |  |  |  |  |  | $ (24,300,000) |  |
Net regulatory liability amount |  |  |  |  |  | $ 22,800,000 |  |
Income Tax Examination, Operating Loss Carryforwards [Abstract] |  |  |  |  |  |  |  |
Valuation allowance |  | $ 546,000 | $ 600,000 | $ 546,000 |  |  |  |
State income taxes [Abstract] |  |  |  |  |  |  |  |
Current |  |  | 1,373,000 | 1,216,000 | $ 2,348,000 |  |  |
Deferred |  |  | 663,000 | 776,000 | (279,000) |  |  |
Total state income tax expense |  |  | 2,036,000 | 1,992,000 | 2,069,000 |  |  |
Federal income taxes [Abstract] |  |  |  |  |  |  |  |
Current |  |  | 2,912,000 | 2,144,000 | 5,725,000 |  |  |
Deferred |  |  | 930,000 | 1,601,000 | (2,110,000) |  |  |
Total federal income tax expense |  |  | 3,842,000 | 3,745,000 | 3,615,000 |  |  |
Reconciliation of effective tax rate [Abstract] |  |  |  |  |  |  |  |
Income before federal and state income taxes |  |  | $ 23,876,000 | $ 22,564,000 | $ 22,501,000 |  |  |
Income before federal and state income taxes |  |  | 100.00% | 100.00% | 100.00% |  |  |
Income Tax Expense (Benefit) [Abstract] |  |  |  |  |  |  |  |
Amount computed at statutory rate |  |  | $ 5,014,000 | $ 4,738,000 | $ 4,725,000 |  |  |
Amount computed at statutory rate |  |  | 21.00% | 21.00% | 21.00% |  | 34.00% |
State income tax-net of federal tax benefit |  |  | $ 1,696,000 | $ 1,600,000 | $ 1,704,000 |  |  |
State income tax-net of federal tax benefit |  |  | 7.10% | 7.10% | 7.60% |  |  |
Regulatory liability adjustment |  |  | $ (450,000) | $ (451,000) | $ (451,000) |  |  |
Regulatory liability adjustment |  |  | (1.90%) | (2.00%) | (2.00%) |  |  |
Other |  |  | $ (382,000) | $ (150,000) | $ (294,000) |  |  |
Other |  |  | (1.60%) | (0.70%) | (1.30%) |  |  |
Total income tax expense |  |  | $ 5,878,000 | $ 5,737,000 | $ 5,684,000 |  |  |
Total effective income tax rate |  |  | 24.60% | 25.40% | 25.30% |  |  |
Deferred tax assets related to [Abstract] |  |  |  |  |  |  |  |
Federal and state operating loss carry-forwards |  | 629,000 | $ 922,000 | $ 629,000 |  |  |  |
Valuation allowance |  | (493,000) | (600,000) | (493,000) |  |  |  |
Bad debt allowance |  | 240,000 | 116,000 | 240,000 |  |  |  |
Stock options |  | 148,000 | 47,000 | 148,000 |  |  |  |
Other |  | 75,000 | 28,000 | 75,000 |  |  |  |
Total deferred tax assets |  | 599,000 | 513,000 | 599,000 |  |  |  |
Deferred tax liabilities related to [Abstract] |  |  |  |  |  |  |  |
Property plant and equipment basis differences |  | (48,536,000) | (52,565,000) | (48,536,000) |  |  |  |
Bond retirement costs |  | (1,210,000) | (1,058,000) | (1,210,000) |  |  |  |
Property taxes |  | (481,000) | (609,000) | (481,000) |  |  |  |
Other |  | (685,000) | (833,000) | (685,000) |  |  |  |
Total deferred tax liabilities |  | (50,912,000) | (55,065,000) | (50,912,000) |  |  |  |
Net deferred tax liability |  | (50,313,000) | (54,552,000) | (50,313,000) |  |  |  |
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense [Abstract] |  |  |  |  |  |  |  |
Balance at beginning of year |  |  | 202,000 | 209,000 |  |  |  |
Additions based on tax positions related to the current year |  |  | 146,000 | 0 |  |  |  |
Additions based on tax positions related to prior years |  |  | 10,000 | 19,000 |  |  |  |
Reductions for tax positions of prior years |  |  | 0 | 0 |  |  |  |
Lapses in statutes of limitations | $ (212,000) | (26,000) | (212,000) | (26,000) |  |  |  |
Balance at end of year |  | 202,000 | $ 146,000 | 202,000 | $ 209,000 |  |  |
Minimum [Member] |  |  |  |  |  |  |  |
Income Tax Examination, Operating Loss Carryforwards [Abstract] |  |  |  |  |  |  |  |
Operating loss carryforwards expiration period |  |  | 2023 |  |  |  |  |
Maximum [Member] |  |  |  |  |  |  |  |
Income Tax Examination, Operating Loss Carryforwards [Abstract] |  |  |  |  |  |  |  |
Operating loss carryforwards expiration period |  |  | 2043 |  |  |  |  |
Valuation Allowance for Deferred Tax Assets [Member] |  |  |  |  |  |  |  |
Valuation Allowances and Reserves [Roll Forward] |  |  |  |  |  |  |  |
Balance at Beginning Of Period |  |  | $ 546,000 | 493,000 | 335,000 |  |  |
Additions Charged to Costs and Expenses |  |  | 54,000 | 53,000 | 158,000 |  |  |
Deductions |  |  | 0 | 0 | 0 |  |  |
Balance at End of Period |  | $ 546,000 | 600,000 | $ 546,000 | $ 493,000 |  |  |
DEPSC [Member] |  |  |  |  |  |  |  |
Income Taxes [Abstract] |  |  |  |  |  |  |  |
Net regulatory liability amount |  |  |  |  |  |  |  | $ 22,200,000
MDPSC [Member] |  |  |  |  |  |  |  |
Income Taxes [Abstract] |  |  |  |  |  |  |  |
Net regulatory liability amount |  |  | 600,000 |  |  |  |  |
State Authorities [Member] |  |  |  |  |  |  |  |
Income Tax Examination, Operating Loss Carryforwards [Abstract] |  |  |  |  |  |  |  |
Net operating loss carry-forwards |  |  | $ 13,800,000 |  |  |  |  |

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