Asset Acquisitions and Divestitures (Summary of Asset Acquisition) (Details) - SWN Upstream Asset Acquisition [Member] $ in Thousands	9 Months Ended
Jun. 30, 2023 USD ($)
Asset Acquisitions and Divestitures [Line Items]
Purchase Price	$ 124,178
Transaction Costs	580
Total Consideration	$ 124,758

Amount of consideration transferred in asset acquisition. Includes, but is not limited to, cash, liability incurred by acquirer, and equity interest issued by acquirer.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 805
-SubTopic 50
-Name Accounting Standards Codification
-Section 55
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479908/805-50-55-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 50
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480060/805-50-25-1

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 50
-Name Accounting Standards Codification
-Section 30
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480027/805-50-30-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 805
-SubTopic 50
-Name Accounting Standards Codification
-Section 30
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480027/805-50-30-2

Name:	us-gaap_AssetAcquisitionConsiderationTransferred
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration