Investment Securities (Schedule Of Credit-Related Loss Activity Recognized In Earnings) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Investments, Debt and Equity Securities [Abstract]
Beginning balance	$ 113	$ 63	$ 175
Plus losses for which other-than-temporary impairment was not previously recognized	4	10	88
Plus losses for which other-than-temporary impairment was previously recognized	28	55	142
Less previously recognized losses related to securities sold	(21)	(13)	(342)
Less losses related to securities intended or required to be sold	0	(2)	0
Ending balance	$ 124	$ 113	$ 63

The cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).

+ References+ Details

This item represents reductions in the amount of cumulative losses recognized in earnings for other than temporary impairments (OTTI) for which a portion of the impairment had been recognized in other comprehensive income (a component of shareholders' equity) due to a change in status of the impaired security because of a change in the entity's intent to either sell the impaired security or it has become more likely than not that the entity will be required to sell the security before recovery of its cost basis.

+ References+ Details