Interest And Other Income (Components Of Interest And Other Income) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Interest and Other Income [Abstract]
Equity interest in income of unconsolidated affiliate	[1]	$ 3	$ 3	$ 5	$ 6
Third-party income (loss) from vertical integration services	[2]	5	(5)	4	(7)
Deferred compensation plan income		0	0	3	2
Other income		3	5	5	6
Total interest and other income		11	3	17	7
GrossRevenuesIncludedInThirdPartyIncomeFromVerticalIntegrationServices		86	104	198	196
GrossExpensesIncludedInThirdPartyIncomeFromVerticalIntegrationServices		$ 81	$ 109	$ 194	$ 203

[1] (a)The Company accounts for its investment in EFS Midstream LLC ("EFS Midstream") using the equity method. EFS Midstream provides gathering, treating and transportation services for the Company.

[2] (b)Income (loss) from vertical integration services primarily represents net margins that result from Company-provided fracture stimulation and service operations, which are ancillary to and supportive of the Company's oil and gas joint operating activities, and do not represent intercompany transactions. For the three and six months ended June 30, 2015, these vertical integration net margins included $86 million and $198 million, respectively, of revenues and $81 million and $194 million, respectively, of costs and expenses. For the same period in 2014, these vertical integration net margins included $104 million and $196 million, respectively, of revenues and $109 million and $203 million, respectively, of costs and expenses.