Derivative and Hedging Instruments (Details-1) $ in Thousands		12 Months Ended
		Dec. 31, 2023 USD ($) Dth1 MWh MW	Dec. 31, 2022 USD ($) Dth1 MWh MW	Dec. 31, 2021 USD ($)
Other Current Assets [Member]
Derivative Fair Values [Abstract]
Derivative fair value, net		$ 1,569	$ 2,747	$ 770
Commodity Contracts And Financial Transimission Rights [Member]
Derivative Fair Values [Abstract]
Derivative fair value, net		$ (5,200)	$ (5,100)
Commodity Contract [Member]
Notional Disclosures [Abstract]
Notional amount, energy measure (in MWh) | MWh		392,000	353,600
Notional amount, decatherm measure (in Dth) | Dth1		7,180,000	8,070,000
Derivative Fair Values [Abstract]
Asset Derivatives, fair value, gross basis		$ 419	$ 2,966
Liability Derivatives, fair value, gross basis		5,824	8,163
Collateral posted against derivative positions		0	0
Commodity Contract [Member] | Other Current Liabilities [Member]
Derivative Fair Values [Abstract]
Asset Derivatives, fair value, gross basis	[1]	263	2,164
Liability Derivatives, fair value, gross basis	[1]	4,942	7,687
Commodity Contract [Member] | Other Deferred Liabilities and Other [Member]
Derivative Fair Values [Abstract]
Asset Derivatives, fair value, gross basis	[1]	156	802
Liability Derivatives, fair value, gross basis	[1]	882	476
Commodity Contract [Member] | Cash Flow Hedging [Member]
Derivative Fair Values [Abstract]
Derivative, right to reclaim collateral (receivable)		$ 5,400	$ 5,200
Financial Transmission Rights [Member]
Notional Disclosures [Abstract]
Notional amount, power measure (in MW) | MW		1,824	1,945
Derivative Fair Values [Abstract]
Asset Derivatives, fair value, gross basis		$ 179	$ 103
Collateral posted against derivative positions		0	0
Financial Transmission Rights [Member] | Other Current Assets [Member]
Derivative Fair Values [Abstract]
Asset Derivatives, fair value, gross basis		179	103
Liability Derivatives, fair value, gross basis		$ 0	$ 0
Energy Related Commodity Contract [Member] | Cash Flow Hedging [Member]
Derivatives, Fair Value [Line Items]
Maximum term of derivative hedging contract		4 years

[1] As of December 31, 2023, and December 31, 2022, collateral of $5.4 million and $5.2 million, respectively, was posted against and netted with derivative liability positions on the consolidated balance sheets. The fair value of the derivative liability disclosed in this table has not been reduced for the collateral posted.