Fair Value of FInancial Instruments Fair Value Options Quantitative Disclosure (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Minimum [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Electricity physical forward purchase	$ 35.00	$ 16.66
Natural gas financial swaps	2.71	2.02
Fnancial swaps - electricity	54.17	26.76
Maximum [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Electricity physical forward purchase	270.00	129.75
Natural gas financial swaps	24.71	8.02
Fnancial swaps - electricity	143.70	68.43
Weighted Average [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Electricity physical forward purchase	101.27	43.73
Natural gas financial swaps	4.42	2.81
Fnancial swaps - electricity	104.21	52.46
Assets [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Electricity physical forward purchase	52,000,000	0
Natural gas financial swaps	6,000,000	5,000,000
Fnancial swaps - electricity	11,000,000	1,000,000
Total commodity contracts	69,000,000	6,000,000
Liabilities [Member]
Fair Value, Option, Quantitative Disclosures [Line Items]
Electricity physical forward purchase	93,000,000	90,000,000
Natural gas financial swaps	8,000,000	1,000,000
Fnancial swaps - electricity	0	0
Total commodity contracts	$ 101,000,000	$ 91,000,000