Fair Value Measurements - Significant Unobservable Inputs Used to Value Level 3 Instruments (Details 2) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) $ / MWh $ / MMBTU	Dec. 31, 2022 USD ($) $ / MMBTU $ / MWh
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Assets	$ 1,570,845	$ 1,552,870
Liabilities		42,446
Level 3
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Assets	6,616	26,132
Liabilities		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	6,616	26,132
Liabilities	$ 1,695	$ 31,020
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	158.08	163.92
Natural gas forward price (in usd per MMBTu) | $ / MMBTU	0.03	(5.08)
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	0.00	(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	259.04	310.69
Natural gas forward price (in usd per MMBTu) | $ / MMBTU	0.08	0
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	$ 6,587	$ 26,132
Liabilities	658	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	29	0
Liabilities	$ 1,037	$ 29,261