DEBT, Long-Term Debt (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Long-term debt consists of [Abstract]
Long term debt	$ 177,622	$ 144,850
Less: current maturities (principal amount)	2,003	1,591
Total long-term debt	175,619	143,259
Payments of principal amounts due during the next five years and thereafter [Abstract]
2023	2,003
2024	2,070
2025	2,037
2026	2,000
2027	2,042
Thereafter	167,470
Asset Purchase-Contractual Obligation [Member]
Payments of principal amounts due during the next five years and thereafter [Abstract]
2023	314
2024	314
2025	314
2026	314
2027	313
Thereafter	0
First Mortgage Bonds [Member]
Long-term debt consists of [Abstract]
Long term debt	156,600	127,200
Payments of principal amounts due during the next five years and thereafter [Abstract]
2023	600
2024	600
2025	600
2026	600
2027	600
Thereafter	153,600
First Mortgage Bonds [Member] \| Series R [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 25,000	25,000
Interest rate, stated percentage	5.96%
Maturity date	Dec. 31, 2028
First Mortgage Bonds [Member] \| Series S [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 6,600	7,200
Interest rate, stated percentage	4.45%
Maturity date	Dec. 31, 2033
First Mortgage Bonds [Member] \| Series T [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 40,000	40,000
Interest rate, stated percentage	4.24%
Maturity date	Dec. 20, 2036
First Mortgage Bonds [Member] \| Series U [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 25,000	25,000
Interest rate, stated percentage	4.71%
Maturity date	Jan. 31, 2038
First Mortgage Bonds [Member] \| Series V [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 30,000	30,000
Interest rate, stated percentage	4.42%
Maturity date	Oct. 31, 2049
First Mortgage Bonds [Member] \| Series W [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 30,000	0
Interest rate, stated percentage	4.43%
Maturity date	Apr. 30, 2047
State Revolving Fund Loans [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 8,975	6,762
Payments of principal amounts due during the next five years and thereafter [Abstract]
2023	656
2024	702
2025	643
2026	581
2027	597
Thereafter	5,796
State Revolving Fund Loans [Member] \| 3.57%, due 09/01/2023 [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 102	200
Interest rate, stated percentage	3.57%
Maturity date	Sep. 01, 2023
State Revolving Fund Loans [Member] \| 3.64%, due 05/01/2025 [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 373	513
Interest rate, stated percentage	3.64%
Maturity date	May 01, 2025
State Revolving Fund Loans [Member] \| 3.41%, due 02/01/2031 [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 1,577	1,735
Interest rate, stated percentage	3.41%
Maturity date	Feb. 01, 2031
State Revolving Fund Loans [Member] \| 3.40%, due 07/01/2032 [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 1,590	1,729
Interest rate, stated percentage	3.40%
Maturity date	Jul. 01, 2032
State Revolving Fund Loans [Member] \| 1.187% due 11/01/2041 [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 617	646
Interest rate, stated percentage	1.187%
Maturity date	Nov. 01, 2041
State Revolving Fund Loans [Member] \| 1.187% due 11/01/2041 [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 724	758
Interest rate, stated percentage	1.187%
Maturity date	Nov. 01, 2041
State Revolving Fund Loans [Member] \| 1.187% due 11/01/2041 [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 1,128	1,181
Interest rate, stated percentage	1.187%
Maturity date	Nov. 01, 2041
State Revolving Fund Loans [Member] \| 2.00% Due 02/01/2043 [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 846	0
Interest rate, stated percentage	2.00%
Maturity date	Feb. 01, 2043
State Revolving Fund Loans [Member] \| 2.00% Due 02/01/2043 [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 974	0
Interest rate, stated percentage	2.00%
Maturity date	Feb. 01, 2043
State Revolving Fund Loans [Member] \| 2.00% Due 06/01/2043 [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 1,044	0
Interest rate, stated percentage	2.00%
Maturity date	Jun. 01, 2043
State Revolving Fund Loans [Member] \| Promissory Note [Member]
Payments of principal amounts due during the next five years and thereafter [Abstract]
2023	$ 433
2024	454
2025	480
2026	505
2027	532
Thereafter	8,074
Notes Payable [Member]
Long-term debt consists of [Abstract]
Long term debt	12,047	10,888
Notes Payable [Member] \| Promissory Note [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 10,478	10,888
Interest rate, stated percentage	5.12%
Maturity date	Dec. 30, 2028
Notes Payable [Member] \| Asset Purchase-Contractual Obligation [Member]
Long-term debt consists of [Abstract]
Long term debt	$ 1,569	$ 0
Interest rate, stated percentage	2.00%
Maturity date	May 26, 2027

Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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