Consolidated Statement of Shareholder's Interest (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Stockholders' Interest [Roll Forward]
Balance at beginning of period			$ 9,653	$ 8,896
Net Income (Loss) Attributable to Parent	272	355	911	946
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Purchase of Interest by Parent			3	0
Other Comprehensive Income (Loss), Net of Tax	176	185	(62)	141
Capital Distributions Cash And Distributions Of Earnings To Parent			(56)	(600)
Balance at end of period	10,449	9,383	10,449	9,383
Shareholder's Interest [Member]
Stockholders' Interest [Roll Forward]
Balance at beginning of period			5,274	5,274
Net Income (Loss) Attributable to Parent			0	0
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Purchase of Interest by Parent			3	0
Other Comprehensive Income (Loss), Net of Tax			(60)	0
Capital Distributions Cash And Distributions Of Earnings To Parent			0	0
Balance at end of period	5,217	5,274	5,217	5,274
Accumulated Other Comprehensive Income (Loss) (Note 10) [Member]
Stockholders' Interest [Roll Forward]
Balance at beginning of period			743	600
Net Income (Loss) Attributable to Parent			0	0
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Purchase of Interest by Parent			0	0
Other Comprehensive Income (Loss), Net of Tax			(2)	141
Capital Distributions Cash And Distributions Of Earnings To Parent			0	0
Balance at end of period	741	741	741	741
Retained Earnings [Member]
Stockholders' Interest [Roll Forward]
Balance at beginning of period			3,636	3,022
Net Income (Loss) Attributable to Parent			911	946
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Purchase of Interest by Parent			0	0
Other Comprehensive Income (Loss), Net of Tax			0	0
Capital Distributions Cash And Distributions Of Earnings To Parent			(56)	(600)
Balance at end of period	$ 4,491	$ 3,368	$ 4,491	$ 3,368