Consolidated Statement of Comprehensive Income (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Net income	$ 352	$ 250
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax	(73)	50
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	(71)	(101)
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	20	(24)
Other Comprehensive Income (Loss), Net of Tax	(124)	(75)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 228	$ 175