Other Expense (Schedule Of Components Of Other Expense) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Restructuring Cost and Reserve [Line Items]
Transportation commitment charges	$ 40	$ 34
Asset Impairment Charges	32	0
Restructuring charges (Note 3)	13	0
Accelerated depreciation	23	0
Loss from vertical integration services	20	6
Other	10	13
Legal and environmental charges	5	4
Idle drilling and well service equipment expense	4	0
Total other expense	147	57
Vertical integration net margins, revenue	35	34
Vertical integration net margins, costs and expenses	55	$ 40
Sand mine
Restructuring Cost and Reserve [Line Items]
Accelerated depreciation	23
Loss from vertical integration services	9
Impairment of inventory and other property and other equipment	16
Pressure pumping assets
Restructuring Cost and Reserve [Line Items]
Loss from vertical integration services	15
Impairment of inventory and other property and other equipment	$ 15