Non-U.S. Activities (Summary Of Non-U.S. Assets) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Interest-bearing deposits with banks	$ 75,796	$ 64,257
Other assets	23,989	25,990
Total assets	256,663	243,291
Non-U.S. Assets
Segment Reporting Information [Line Items]
Interest-bearing deposits with banks	10,281	9,584
Investment securities	31,790	31,522
Other assets	17,552	16,778
Total assets	$ 59,623	$ 57,884