Loans - Consumer Loans excluding Credit Card, Trial Modifications (Details 6e) (Consumer Portfolio Segment, Residential real estate, excluding PCI [Member], USD $) In Millions, unless otherwise specified	Sep. 30, 2011
Financing Receivable, Trial Modifications [Line Items]
Amount of loans in a trial modification period	$ 900
Trial Modifications Since Mid 2010 [Member]
Financing Receivable, Trial Modifications [Line Items]
Percentage of trial modifications resulting in completed modifications	74.00%
Trial modifications that did not successfully complete the trial period	22.00%
Percentage of trial modifications still in the trial period	4.00%