Derivative Financial Instruments (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011		Jun. 30, 2012	Jun. 30, 2011
Gains and losses on derivative instruments designated and qualifying as hedging instruments in fair value hedges
Gain (loss) on fair value hedges recognized in earnings	$ (633)	$ (376)		$ (390)	$ (333)
Other income [Member]
Gains and losses on derivative instruments designated and qualifying as hedging instruments in fair value hedges
Gain (loss) on fair value hedges recognized in earnings	(581)	(369)		(279)	(324)
Other income [Member] | Interest rate contracts [Member]
Gains and losses on derivative instruments designated and qualifying as hedging instruments in fair value hedges
Gain (loss) on fair value hedges recognized in earnings	(581)	(369)	[1]	(279)	(324)
Interest Income [Member] | Interest rate contracts [Member]
Gains and losses on derivative instruments designated and qualifying as hedging instruments in fair value hedges
Gain (loss) on fair value hedges recognized in earnings	$ (52)	$ (7)		$ (111)	$ (9)

[1] During the three and six months ended June 30, 2012 and 2011, there were no other-than-temporary impairment (“OTTI”) losses on securities recognized in other revenues and no OTTI losses in the non-credit component on securities were recognized in accumulated other comprehensive income.