Derivative Instruments - Gross Derivative and Offset (Details) - Derivatives not designated as hedging instruments: - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Assets
Gross Amounts Recognized	$ 2,000	$ 0
Gross Amount Offset	(2,000)	0
Net Amount	0	0
Derivative Liability [Abstract]
Gross Amounts Recognized	7,000	12,000
Gross Amount Offset	(2,000)	0
Net Amount	5,000	12,000
CERC
Assets
Gross Amounts Recognized	2,000	0
Gross Amount Offset	(2,000)	0
Net Amount	0	0
Derivative Liability [Abstract]
Gross Amounts Recognized	6,000	11,000
Gross Amount Offset	(2,000)	0
Net Amount	4,000	11,000
Natural gas derivatives \| Current Assets: Non-trading derivative assets
Assets
Gross Amounts Recognized	2,000	0
Gross Amount Offset	(2,000)	0
Net Amount	0	0
Natural gas derivatives \| Current Assets: Non-trading derivative assets \| CERC
Assets
Gross Amounts Recognized	2,000	0
Gross Amount Offset	(2,000)	0
Net Amount	0	0
Natural gas derivatives \| Current Liabilities: Non-trading derivative liabilities
Assets
Gross Amounts Recognized	0	0
Derivative Liability [Abstract]
Gross Amounts Recognized	6,000	9,000
Gross Amount Offset	(2,000)	0
Net Amount	4,000	9,000
Natural gas derivatives \| Current Liabilities: Non-trading derivative liabilities \| CERC
Assets
Gross Amounts Recognized	0	0
Derivative Liability [Abstract]
Gross Amounts Recognized	5,000	8,000
Gross Amount Offset	(2,000)	0
Net Amount	3,000	8,000
Natural gas derivatives \| Other Liabilities: Non-trading derivative liabilities
Assets
Gross Amounts Recognized	0	0
Derivative Liability [Abstract]
Gross Amounts Recognized	1,000	3,000
Gross Amount Offset	0	0
Net Amount	1,000	3,000
Natural gas derivatives \| Other Liabilities: Non-trading derivative liabilities \| CERC
Assets
Gross Amounts Recognized	0	0
Derivative Liability [Abstract]
Gross Amounts Recognized	1,000	3,000
Gross Amount Offset	0	0
Net Amount	$ 1,000	$ 3,000

Fair value, after effect of master netting arrangement, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and contract can be net settled by means outside contract or delivery of asset. Includes derivative subject to master netting arrangement not elected or qualified to offset. Excludes derivative not subject to master netting arrangement or similar agreement.

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Fair value of liability associated with financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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