Discontinued Operations (Amounts Reported as Discontinued Operations in the Consolidated Statements of Comprehensive Earnings) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Oil, gas and NGL sales	$ 263	$ 1,227	$ 1,592
Oil, gas and NGL derivatives		(113)	150
Marketing and midstream revenues		38	3,662
Total revenues	263	1,152	5,404
Production expenses	214	599	1,072
Exploration expenses		13	48
Marketing and midstream expenses		18	2,954
Depreciation, depletion and amortization		205	674
Asset impairment charges	182	785
Asset dispositions	1	(222)	(2,593)
General and administrative expenses	3	34	141
Financing costs, net	(3)	87	112
Restructuring and transaction costs	9	248	17
Other expenses	9	17	140
Total expenses	415	1,784	2,565
Earnings (loss) from discontinued operations before income taxes	(152)	(632)	2,839
Income tax expense (benefit)	(24)	(358)	329
Net earnings (loss) from discontinued operations, net of tax	(128)	(274)	2,510
Net earnings attributable to noncontrolling interests			160
Net earnings (loss) from discontinued operations, attributable to Devon			2,350
Net earnings (loss) from discontinued operations, attributable to Devon			2,350
Barnett Shale [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Oil, gas and NGL sales	263	486	777
Total revenues	263	486	777
Production expenses	214	306	467
Depreciation, depletion and amortization		77	100
Asset impairment charges	182	748
Asset dispositions	(4)	1	14
Other expenses	10	11	(34)
Total expenses	402	1,143	547
Earnings (loss) from discontinued operations before income taxes	(139)	(657)	230
Income tax expense (benefit)	(11)	(142)	50
Net earnings (loss) from discontinued operations, net of tax	(128)	(515)	180
Net earnings (loss) from discontinued operations, attributable to Devon			180
Net earnings (loss) from discontinued operations, attributable to Devon			180
Canada [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Oil, gas and NGL sales		741	814
Oil, gas and NGL derivatives		(113)	151
Marketing and midstream revenues		38	95
Total revenues		666	1,060
Production expenses		293	605
Exploration expenses		13	48
Marketing and midstream expenses		18	42
Depreciation, depletion and amortization		128	330
Asset impairment charges		37
Asset dispositions	5	(223)
General and administrative expenses	3	34	76
Financing costs, net	(3)	87	14
Restructuring and transaction costs	9	248	17
Other expenses	(1)	6	182
Total expenses	13	641	1,314
Earnings (loss) from discontinued operations before income taxes	(13)	25	(254)
Income tax expense (benefit)	$ (13)	(216)	(124)
Net earnings (loss) from discontinued operations, net of tax		$ 241	(130)
Net earnings (loss) from discontinued operations, attributable to Devon			(130)
Net earnings (loss) from discontinued operations, attributable to Devon			(130)
EnLink and General Partner [Member]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Marketing and midstream revenues			3,567
Total revenues			3,567
Marketing and midstream expenses			2,912
Depreciation, depletion and amortization			244
Asset dispositions			(2,607)
General and administrative expenses			65
Financing costs, net			98
Other expenses			(8)
Total expenses			704
Earnings (loss) from discontinued operations before income taxes			2,863
Income tax expense (benefit)			403
Net earnings (loss) from discontinued operations, net of tax			2,460
Net earnings attributable to noncontrolling interests			160
Net earnings (loss) from discontinued operations, attributable to Devon			2,300
Net earnings (loss) from discontinued operations, attributable to Devon			$ 2,300