SUBSEQUENT EVENTS	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTSOn November 3, 2021, Southwestern entered into an Agreement and Plan of Merger with Mustang Acquisition Company, LLC (“Merger Sub”), GEP Haynesville LLC (“GEPH”) and GEPH Unitholder Rep, LLC, the Unitholder representative, (the “GEPH Merger Agreement”). Pursuant to the terms of the GEPH Merger Agreement, GEPH will merge with and into Merger Sub, a subsidiary of Southwestern, with GEPH surviving the merger (the “GEPH Merger”). Under the terms and conditions of the GEPH Merger Agreement, on the closing date, each issued and outstanding Preferred Unit (as defined in the GEPH Merger Agreement) will be redeemed in full for an aggregate amount in cash equal to $1,165 million. The aggregate consideration to be paid to the holders of GEPH units in the transaction will consist of $160 million in cash and 99,337,748 shares of Southwestern common stock, which shares have an aggregate dollar value equal to $525 million based on the volume weighted average sales price as traded on the New York Stock Exchange of such shares calculated for the thirty trading day period ending on November 2, 2021. The cash consideration and stock consideration are subject to adjustment as provided in the GEPH Merger Agreement. The transaction is expected to close on or around December 31, 2021, subject to customary closing conditions.