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Asset Acquisition and Divestitures [Line Items]

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Deposit paid for the acquisition of Upstream Assets

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ICE Brent Average per Barrel

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Value of Contingent Consideration from Asset Sale

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Purchase price of expected asset acquisition prior to consideration being transferred. Excludes business acquisition.

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Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of, expected to be disposed of after one year or the normal operating cycle, if longer.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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The cash inflow to dispose of long-lived, physical assets and mineral interests in oil and gas properties used for normal oil and gas operations.

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Asset Acquisitions and Divestitures (Narrative) (Details) - USD ($)	6 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Sep. 30, 2022	Jun. 30, 2022
Asset Acquisitions and Divestitures [Line Items]
Deposit Paid for Upstream Assets	$ 12,700,000	$ 0
Net Proceeds from Sale of Oil and Gas Producing Properties	0	$ 13,525,000
SWN Upstream Asset Acquisition [Member]
Asset Acquisitions and Divestitures [Line Items]
Consideration for Asset Acquisition of Upstream Assets	127,000,000
Deposit Paid for Upstream Assets	12,700,000
California Asset Sale [Member]
Asset Acquisitions and Divestitures [Line Items]
Consideration for Asset Sale				$ 253,500,000
Net Proceeds from Sale of Oil and Gas Producing Properties			$ 240,900,000
Maximum Annual Contingent Payments				10,000,000
Amount of Each Incremental Contingent Payment				1,000,000
Incremental Dollar Per Barrel That ICE Brent Average Exceeds Price				1
Gain on Sale of Assets			12,700,000
Asset Retirement Obligation Reduction			50,100,000
California Asset Sale [Member] \| Minimum [Member]
Asset Acquisitions and Divestitures [Line Items]
ICE Brent Average per Barrel				95
California Asset Sale [Member] \| Maximum [Member]
Asset Acquisitions and Divestitures [Line Items]
ICE Brent Average per Barrel				105
California Asset Sale [Member] \| Present Value of Contingent Consideration [Member]
Asset Acquisitions and Divestitures [Line Items]
Value of Contingent Consideration from Asset Sale	$ 5,900,000		$ 8,200,000	12,600,000
Full Cost Method of Accounting Assets [Member] \| California Asset Sale [Member]
Asset Acquisitions and Divestitures [Line Items]
Property, Plant and Equipment Disposal				220,700,000
Assets Not Subject to Full Cost Method of Accounting [Member] \| California Asset Sale [Member]
Asset Acquisitions and Divestitures [Line Items]
Property, Plant and Equipment Disposal				$ 32,800,000