Fair Value Measurements - Significant Unobservable Inputs Used to Value Level 3 Instruments (Details) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2024 USD ($) $ / MWh $ / MMBTU	Dec. 31, 2023 USD ($) $ / MMBTU $ / MWh
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Assets, Fair Value Disclosure	$ 1,614,173	$ 1,570,845
Level 3
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Assets, Fair Value Disclosure	238	6,616
Commodity Contracts | Level 3 | Forward Contracts
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Assets, Fair Value Disclosure	238	6,616
Liabilities, Fair Value Disclosure	$ 21,878	$ 1,695
Commodity Contracts | Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | 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	25.27	37.79
Natural gas forward price (in usd per MMBTu) | $ / MMBTU	(0.10)	0.00
Commodity Contracts | Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | 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	240.98	259.04
Natural gas forward price (in usd per MMBTu) | $ / MMBTU	0	0.08
Commodity Contracts | Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | 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	142.10	158.08
Natural gas forward price (in usd per MMBTu) | $ / MMBTU	(0.04)	0.03
Commodity Option | Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | 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	43.90
Electricity price volatilities	2.35
Natural gas price volatilities	0.65
Commodity Option | Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | 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	68.60
Electricity price volatilities	3.84
Natural gas price volatilities	0.86
Commodity Option | Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow | 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	53.66
Electricity price volatilities	2.96
Natural gas price volatilities	0.78
Electricity | Commodity Contracts | Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Assets, Fair Value Disclosure	$ 238	$ 6,587
Liabilities, Fair Value Disclosure	19,228	658
Electricity | Commodity Option | Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Assets, Fair Value Disclosure	0
Liabilities, Fair Value Disclosure	573
Natural Gas | Commodity Contracts | Level 3 | Forward Contracts | Valuation Technique, Discounted Cash Flow
Information regarding the entity's internally developed significant unobservable inputs used to value its level 3 instruments
Assets, Fair Value Disclosure	0	29
Liabilities, Fair Value Disclosure	$ 2,077	$ 1,037