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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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The effective interest rate at the end of the reporting period.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Long-Term Debt (Narrative) (Details) - USD ($)	12 Months Ended
Long-Term Debt (Narrative) (Details) - USD ($)	Dec. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Amortization of deferred costs	$ 36,000	$ 36,000
Unamortized debt issuance expense	$ 266,000
Credit facility participation fee and fronting fee percentage	0.25%
Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage	0.25%
Line of credit facility, remaining borrowing capacity	$ 45,000,000	$ 50,000,000
Revolving Credit Facility \| Variable income interest rate
Debt Instrument [Line Items]
Interest rates under Credit Facility	4.49%
Minimum \| Base Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.00%
Minimum \| Variable income interest rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.00%
Minimum \| Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage	0.20%
Maximum \| Base Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	1.00%
Maximum \| Variable income interest rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.00%
Maximum \| Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage	0.30%
Second Amendment \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt issuance costs	$ 120,000
Revolving Credit Facility \| Third Amendment
Debt Instrument [Line Items]
Debt issuance costs	$ 161,000