Discontinued Operations (Amounts Reported as Discontinued Operations in the Consolidated Statements of Comprehensive Earnings) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($)
Discontinued Operations And Disposal Groups [Abstract]
Oil, gas and NGL sales	$ 92
Total revenues	92
Production expenses	74
Asset impairment charges	179	[1]
General and administrative expenses	1
Financing costs, net	(2)
Other, net	(3)
Total expenses	249
Loss from discontinued operations before income taxes	(157)
Income tax expense (benefit)	(32)
Net loss from discontinued operations, net of tax	$ (125)

[1] Devon recognized an $179 million asset impairment in the first quarter of 2020 related to the Barnett Shale assets primarily due to the difference between the net carrying value and the purchase price, net of estimated customary purchase price adjustments, which qualified as a level 2 fair value measurement.