Number of shares of equity interests issued or issuable to acquire entity.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

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- Definition

Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477

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- Definition

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.

+ References

No definition available.

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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Earnings Per Share (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions			1 Months Ended
	Dec. 31, 2021	Sep. 01, 2021	Sep. 30, 2021
GEPH Merger
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Shares of Southwestern common stock issued (in shares)	99,337,748
Value of Southwestern's stock issued as consideration	$ 463
NYSE closing price per share of Southwestern common shares (in dollars per share)	$ 4.66
Indigo Natural Resources, LLC
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Shares of Southwestern common stock issued (in shares)		337,827,171	337,827,171
Value of Southwestern's stock issued as consideration			$ 1,588
NYSE closing price per share of Southwestern common shares (in dollars per share)		$ 4.70