Fair Value Measurements (Details 5) (USD $) In Millions, unless otherwise specified			6 Months Ended								6 Months Ended			6 Months Ended
	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2012 Loss severity rates [Member]		Jun. 30, 2012 Loss severity rates [Member] Minimum [Member]	Jun. 30, 2012 Loss severity rates [Member] Maximum [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 3 [Member] Loss severity rates [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 3 [Member] Third Party Appraisal on Residential Mortgage Loan [member]	Jun. 30, 2012 Fair Value, Inputs, Level 3 [Member] Third Party Appraisal on Impaired Loans [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 3 [Member] Residential Mortgage [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 3 [Member] Residential Mortgage [Member] Minimum [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 3 [Member] Residential Mortgage [Member] Maximum [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 3 [Member] Impaired Loans [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 3 [Member] Impaired Loans [Member] Minimum [Member]	Jun. 30, 2012 Fair Value, Inputs, Level 3 [Member] Impaired Loans [Member] Maximum [Member]
Quantitative Information About Non Recurring Fair Value Measurement Of Assets And Liabilities
Fair Value	$ 98,359	$ 93,733								$ 188			$ 289
Valuation Technique(s)								Valuation of third party appraisal on underlying collateral	Valuation by third party appraisal on underlying collateral
Significant Unobservable Inputs			Loss severity rates	[1]			Loss severity rates
Range of Inputs					50.00%	100.00%					30.00%	70.00%		3.00%	100.00%

[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.