Organization and Summary of Significant Accounting Policies (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Disclosure Organization And Summary Of Significant Accounting Policies [Line Items]
Consideration transferred in the merger	$ 18,000,000,000		$ 18,000,000,000
Excise taxes
Excise taxes	77,000,000	76,000,000	146,000,000	149,000,000
Consolidation of variable interest entities
Miscellaneous other property and investments	12,000,000		12,000,000		12,000,000
Cash and cash equivalents	2,000,000		2,000,000		1,000,000
VIE - exposure to loss from capital lease agreements	8,000,000		8,000,000
VIE - activity with VIE related to lease payments	1,000,000	1,000,000	1,000,000	1,000,000
PEC
Excise taxes
Excise taxes	26,000,000	25,000,000	52,000,000	53,000,000
Consolidation of variable interest entities
Miscellaneous other property and investments	12,000,000		12,000,000		12,000,000
Cash and cash equivalents	2,000,000		2,000,000		1,000,000
VIE - exposure to loss from capital lease agreements	8,000,000		8,000,000
VIE - activity with VIE related to lease payments	1,000,000	1,000,000	1,000,000	1,000,000
PEF
Excise taxes
Excise taxes	$ 51,000,000	$ 51,000,000	$ 94,000,000	$ 96,000,000