Derivative and Hedging Instruments (Details-1) $ in Thousands		9 Months Ended	12 Months Ended
		Sep. 30, 2024 USD ($) Dth1 MWh MW	Dec. 31, 2023 USD ($) Dth1 MWh MW
Derivative fair values [Abstract]
Derivative, right to reclaim collateral		$ 1,500	$ 5,400
Commodity Contracts And Financial Transimission Rights [Member]
Derivative fair values [Abstract]
Derivative, Fair Value, Net		$ (1,500)	$ (5,200)
Commodity Contract [Member]
Gross Notional Volume of Open Derivatives [Abstract]
Notional amount, energy measures (in MWh) | MWh		269,120	392,000
Notional amount, decatherm measure (in Dth) | Dth1		7,900,000	7,180,000
Derivative fair values [Abstract]
Derivative Asset, Fair Value, Gross Asset		$ 975	$ 419
Derivative Liability, Fair Value, Gross Liability		2,460	5,824
Collateral posted against derivative positions		0	0
Derivative, right to reclaim collateral		1,485	5,405
Commodity Contract [Member] | Other Current Liabilities [Member]
Derivative fair values [Abstract]
Derivative Asset, Fair Value, Gross Asset	[1]	891	263
Derivative Liability, Fair Value, Gross Liability	[1]	2,199	4,942
Commodity Contract [Member] | Other Deferred Liabilities and Other [Member]
Derivative fair values [Abstract]
Derivative Asset, Fair Value, Gross Asset	[1]	84	156
Derivative Liability, Fair Value, Gross Liability	[1]	261	882
Commodity Contract [Member] | Cash Flow Hedging [Member]
Derivative fair values [Abstract]
Derivative, right to reclaim collateral		$ 1,500	$ 5,400
Energy Related Commodity Contract [Member] | Cash Flow Hedging [Member]
Derivatives, Fair Value [Line Items]
Maximum term of derivative hedging contract		4 years
Financial Transmission Rights [Member]
Gross Notional Volume of Open Derivatives [Abstract]
Notional amount, power measure (in MW) | MW		3,276	1,824
Derivative fair values [Abstract]
Derivative Asset, Fair Value, Gross Asset			$ 179
Derivative Liability, Fair Value, Gross Liability		$ 17
Collateral posted against derivative positions			0
Derivative, right to reclaim collateral		17
Financial Transmission Rights [Member] | Other Current Assets/Liabilities
Derivative fair values [Abstract]
Derivative Asset, Fair Value, Gross Asset		0	179
Derivative Liability, Fair Value, Gross Liability		$ 17	$ 0

[1] As of September 30, 2024, and December 31, 2023, collateral of $1.5 million and $5.4 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.