Share-Based Compensation (Schedule Of Share-Based Compensation Expense Included In The Consolidated Comprehensive Statements Of Earnings) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 196	$ 161	$ 230
Related income tax benefit	6	6	67
Devon [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	148	130	194
General Partner And EnLink [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	48	31	36
G&A [Member] | Devon [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	141	124	185
G&A [Member] | General Partner And EnLink [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	37	24	31
Exploration Expenses [Member] | Devon [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	7	6	9
Marketing And Midstream Expenses [Member] | General Partner And EnLink [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 11	$ 7	$ 5