Loans and Allowance for Loan Losses (Employee Loans) (Details) - Employee Retainment and Recruitment Program - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2015	Dec. 31, 2014
Employee Loans
Employee loans outstanding	$ 4,887	$ 5,130
Allowance for employee loans	$ 121	$ 116
Minimum
Employee Loans
Employee loan repayment terms	1 year
Maximum
Employee Loans
Employee loan repayment terms	12 years

For an unclassified balance sheet, amounts due from an Entity employee, not to include stockholders or officers.

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