Summary Of Significant Accounting Policies (Narrative) (Details) $ in Millions		3 Months Ended
	Jan. 07, 2021	Mar. 31, 2022 USD ($) a	Mar. 31, 2021 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Restricted cash		$ 166	$ 195
Barnett Shale [Member]
Summary Of Significant Accounting Policies [Line Items]
Cash payments for divestitures		10
Canada [Member] | Barnett Shale [Member]
Summary Of Significant Accounting Policies [Line Items]
Restricted cash		$ 150
Devon and WPX Agreement [Member]
Summary Of Significant Accounting Policies [Line Items]
Date of agreement	Jan. 07, 2021	Jan. 07, 2021
Conversion of common stock into right to recieve per share	0.5165
WPX and Howard Energy Partners [Member]
Summary Of Significant Accounting Policies [Line Items]
Voting interest in the join venture legal entity		50.00%
Catalyst [Member]
Summary Of Significant Accounting Policies [Line Items]
Area of land | a		50,000