Fair Value Measurements - Significant Unobservable Inputs Used to Value Level 3 Instruments (Details 2) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2023 USD ($) $ / MWh $ / MMBTU	Dec. 31, 2022 USD ($) $ / MWh $ / MMBTU
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Assets	$ 1,511,685	$ 1,552,870
Liabilities	99,257	42,446
Level 3
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Assets	21,257	26,132
Liabilities	14,635	31,020
Level 3 | Forward Contracts | Commodity Contracts
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Assets	21,257	26,132
Liabilities	$ 14,635	$ 31,020
Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | Commodity Contracts | Minimum
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Electricity forward price (in usd per MWh) | $ / MWh	37.79	37.79
Natural gas forward price (in usd per MMBTu) | $ / MMBTU	(0.02)	(11.81)
Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | Commodity Contracts | Maximum
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Electricity forward price (in usd per MWh) | $ / MWh	306.34	310.69
Natural gas forward price (in usd per MMBTu) | $ / MMBTU	0.14	0.00
Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | Commodity Contracts | Weighted-Average
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Electricity forward price (in usd per MWh) | $ / MWh	157.00	163.92
Natural gas forward price (in usd per MMBTu) | $ / MMBTU	0.02	(5.08)
Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | Electricity | Commodity Contracts
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Assets	$ 21,084	$ 26,132
Liabilities	14,385	1,759
Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | Natural Gas | Commodity Contracts
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Assets	173	0
Liabilities	$ 250	$ 29,261