Net Earnings (Loss) Per Share Attributable To Devon (Earnings Per Share Computations) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016		Dec. 31, 2015
Net earnings (loss):
Net earnings (loss) attributable to Devon		$ 898	$ (1,056)	[1]	$ (12,896)	[1]
Attributable to participating securities		(10)	(2)		(5)
Basic and diluted earnings (loss)		$ 888	$ (1,058)		$ (12,901)
Common shares:
Common shares outstanding - total		525	513		412
Attributable to participating securities		(5)	(6)		(5)
Common shares outstanding - basic		520	507		407
Dilutive effect of potential common shares issuable		3
Common shares outstanding - diluted		523	507		407
Net earnings (loss) per share attributable to Devon:
Basic		$ 1.71	$ (2.09)	[1]	$ (31.72)	[1]
Diluted		$ 1.70	$ (2.09)	[1]	$ (31.72)	[1]
Antidilutive options	[2]	2	3		4

[1] Prior year amounts have been recast due to change in accounting principle. See Note 2 in “Item 8. Financial Statements and Supplementary Data” of this report.

[2] Amounts represent options to purchase shares of Devon’s common stock that are excluded from the diluted net earnings per share calculations because the options are antidilutive.