Derivative and Hedging Instruments (Details-1) $ in Thousands		6 Months Ended	12 Months Ended
		Jun. 30, 2023 USD ($) Dth1 MWh MW	Dec. 31, 2022 USD ($) Dth1 MWh MW	Mar. 31, 2023 USD ($)	Jun. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Other Current Assets [Member]
Derivative fair values [Abstract]
Derivative, Fair Value, Net		$ 1,074	$ 2,747	$ 455	$ (161)	$ 267	$ 770
Commodity Contracts And Financial Transimission Rights [Member]
Derivative fair values [Abstract]
Derivative, Fair Value, Net		$ (5,000)	$ (5,100)
Commodity Contract [Member]
Gross Notional Volume of Open Derivatives [Abstract]
Notional amount, energy measures (in MWh) | MWh		391,760	353,600
Notional amount, decatherm measure (in Dth) | Dth1		6,960,000	8,070,000
Derivative fair values [Abstract]
Derivative Asset, Fair Value, Gross Asset		$ 1,044	$ 2,966
Derivative Liability, Fair Value, Gross Liability		6,462	8,163
Collateral posted against derivative positions		0	0
Commodity Contract [Member] | Other Current Liabilities [Member]
Derivative fair values [Abstract]
Derivative Asset, Fair Value, Gross Asset	[1]	1,016	2,164
Derivative Liability, Fair Value, Gross Liability	[1]	5,881	7,687
Commodity Contract [Member] | Other Deferred Liabilities and Other [Member]
Derivative fair values [Abstract]
Derivative Asset, Fair Value, Gross Asset	[1]	28	802
Derivative Liability, Fair Value, Gross Liability	[1]	581	476
Commodity Contract [Member] | Cash Flow Hedging [Member]
Derivative fair values [Abstract]
Derivative, right to reclaim collateral (receivable)		$ 5,400	$ 5,200
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		4,018	1,945
Derivative fair values [Abstract]
Derivative Asset, Fair Value, Gross Asset		$ 401	$ 103
Collateral posted against derivative positions		0	0
Financial Transmission Rights [Member] | Other Current Assets [Member]
Derivative fair values [Abstract]
Derivative Asset, Fair Value, Gross Asset		401	103
Derivative Liability, Fair Value, Gross Liability		$ 0	$ 0

[1] As of June 30, 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.