Commitments and Contingencies Qualifying Facilities Liability (Details) - USD ($)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Beginning QF liability	$ 64,943,000
Ending QF liability	49,728,000	$ 64,943,000
Recorded Unconditional Purchase Obligation, Fiscal Year Maturity Schedule [Abstract]
Periodic adjustment of the liability for price escalation	5,400,000
Annual reset of liability to actual output and pricing	1,800,000	2,600,000
Unrecovered Amount, One Time Adjustment Of The Liability based on Contract Terms	7,000,000
Unrecovered Amount, Annual Reset to Actual Output and Pricing, Change year-over-year	$ 800,000
Maximum [Member]
Long term purchase commitments term	24 years
Qualifying Facility Contracts [Member]
Beginning QF liability	$ 64,943,000	81,379,000
Settlements(1)	(20,076,000)	(22,497,000)
Interest expense	4,861,000	6,061,000
Ending QF liability	49,728,000	$ 64,943,000
Qualifying Facility Contracts [Member] \| Minimum [Member]
Price per MWH of energy required to be purchased per QF agreement	64
Qualifying Facility Contracts [Member] \| Maximum [Member]
Price per MWH of energy required to be purchased per QF agreement	136
Qualifying Facility Contracts [Member] \| Gross Obligation [Member]
Recorded Unconditional Purchase Obligation	386,095,000
Recorded Unconditional Purchase Obligation, Fiscal Year Maturity Schedule [Abstract]
2023	80,750,000
2024	76,393,000
2025	60,360,000
2026	55,393,000
2027	56,665,000
Thereafter	56,534,000
Recorded Unconditional Purchase Obligation	386,095,000
Qualifying Facility Contracts [Member] \| Recoverable Amounts [Member]
Recorded Unconditional Purchase Obligation	327,773,000
Recorded Unconditional Purchase Obligation, Fiscal Year Maturity Schedule [Abstract]
2023	61,280,000
2024	60,706,000
2025	52,950,000
2026	46,274,000
2027	46,668,000
Thereafter	59,895,000
Recorded Unconditional Purchase Obligation	327,773,000
Qualifying Facility Contracts [Member] \| Net Amount [Member]
Recorded Unconditional Purchase Obligation	58,322,000
Recorded Unconditional Purchase Obligation, Fiscal Year Maturity Schedule [Abstract]
2023	19,470,000
2024	15,687,000
2025	7,410,000
2026	9,119,000
2027	9,997,000
Thereafter	3,361,000
Recorded Unconditional Purchase Obligation	$ 58,322,000

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Price Per MWH Of Energy Required To Be Purchase Per QF Agreement

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Qualifying Facility Liability

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Unrecovered Amount, Annual Reset to Actual Output and Pricing, Change year-over-year

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Unrecovered amount, annual reset to actual output and pricing of the liability.

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Unrecovered Amount, One Time Adjustment Of The Liability based on Contract Terms

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount of the recorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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Amount of recorded unconditional purchase obligation maturing after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of recorded unconditional purchase obligation to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of recorded unconditional purchase obligation to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of recorded unconditional purchase obligation to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of recorded unconditional purchase obligation to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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