Derivative Instruments - Gas hedges (Details) - Natural gas swaps $ in Thousands, MMBTU in Millions	3 Months Ended
Mar. 31, 2022 USD ($) MMBTU	Dec. 31, 2021 USD ($)
Derivative Instruments
Derivative asset \| $	$ 173,946	$ 63,994
Credit collateral posted \| $	$ 39,200	$ 1,800
Notional volume of natural gas derivatives (in MMBTUs)	111.8
2022
Derivative Instruments
Notional volume of natural gas derivatives (in MMBTUs)	21.6
2023
Derivative Instruments
Notional volume of natural gas derivatives (in MMBTUs)	26.8
2024
Derivative Instruments
Notional volume of natural gas derivatives (in MMBTUs)	25.3
2025
Derivative Instruments
Notional volume of natural gas derivatives (in MMBTUs)	21.2
2026
Derivative Instruments
Notional volume of natural gas derivatives (in MMBTUs)	16.0
2027
Derivative Instruments
Notional volume of natural gas derivatives (in MMBTUs)	0.9

The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Nominal energy measure used to calculate payments on a derivative instrument.

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