Provision (Benefit) for Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income Tax Contingency [Line Items]
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain	$ 2,522	$ 0	$ 2,522	$ 0
Current :
Federal	(15)	25	98	(47)
State	(2)	0	2	3
Foreign	2	2	7	3
Total	(15)	27	107	(41)
Deferred:
Federal	911	21	910	233
State	98	9	103	41
Foreign	4	5	13	27
Total	1,013	35	1,026	301
Total provision (benefit)	998	62	1,133	260
TEXAS [Member]
Deferred:
State				10
Access Midstream Partners Acquisition [Member]
Income Tax Contingency [Line Items]
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain	2,500		2,500
Canada Acquisition [Member]
Income Tax Contingency [Line Items]
Current income tax liabilities associated with undistributed earnings of foreign operations	$ 64		$ 64