Debt And Related Expenses (Schedule of WPX Debt assumed with the Merger) (Details) - WPX $ in Millions	9 Months Ended
	Sep. 30, 2021 USD ($)
Debt Instrument [Line Items]
Face Value	$ 3,257
Fair Value	3,562
6.00% due January 15, 2022 [Member]
Debt Instrument [Line Items]
Face Value	43
Fair Value	44
8.25% due August 1, 2023 [Member]
Debt Instrument [Line Items]
Face Value	242
Fair Value	$ 281
Optional Redemption	Jun. 01, 2023	[1]
5.25% due September 15, 2024 [Member]
Debt Instrument [Line Items]
Face Value	$ 472
Fair Value	$ 530
Optional Redemption	Jun. 15, 2024	[1]
5.75% due June 1, 2026 [Member]
Debt Instrument [Line Items]
Face Value	$ 500
Fair Value	$ 529
Optional Redemption	Jun. 01, 2021	[1]
5.25% due October 15, 2027 [Member]
Debt Instrument [Line Items]
Face Value	$ 600
Fair Value	$ 646
Optional Redemption	Oct. 15, 2022	[1]
5.875% due June 15, 2028 [Member]
Debt Instrument [Line Items]
Face Value	$ 500
Fair Value	$ 554
Optional Redemption	Jun. 15, 2023	[1]
4.50% due January 15, 2030 [Member]
Debt Instrument [Line Items]
Face Value	$ 900
Fair Value	$ 978
Optional Redemption	Jan. 15, 2025	[1]

[1] At any time prior to these dates, Devon has or had the option to redeem (i) some or all of the notes at a specified "make whole" premium and (ii) a portion of certain of the notes at applicable redemption prices, in each case as described in the indenture documents governing the notes to be redeemed. On or after these dates, Devon has or had the option to redeem the notes, in whole or in part, at the applicable redemption prices set forth in the indenture documents, plus accrued and unpaid interest thereon to the redemption date as more fully described in such documents.