XML 32 R55.htm IDEA: XBRL DOCUMENT v2.4.0.8
Allowance for Loan Losses - Accrued Interest Receivable (Detail) (USD $)
In Millions, unless otherwise specified
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Total Accrued Interest Receivable $ 1,023 $ 904 $ 1,018
Greater Than 90 Days Past Due 48 55 54
Allowance for Uncollectible Interest 66 67 72
Private Education Loans - Traditional [Member]
      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Total Accrued Interest Receivable 926 798 870
Greater Than 90 Days Past Due 35 39 36
Allowance for Uncollectible Interest 46 45 44
Private Education Loans - Non-Traditional [Member]
      
Accounts, Notes, Loans and Financing Receivable [Line Items]      
Total Accrued Interest Receivable 97 106 148
Greater Than 90 Days Past Due 13 16 18
Allowance for Uncollectible Interest $ 20 $ 22 $ 28