XML 62 R49.htm IDEA: XBRL DOCUMENT v3.10.0.1
Loans - Additional Information (Detail) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Jun. 30, 2018
Sep. 30, 2018
Sep. 30, 2017
Dec. 31, 2017
Loans and Leases Receivable Disclosure [Line Items]        
Transfer of Portfolio Loans and Leases to Held-for-sale   $ 779 $ 449  
Loans and Leases Receivable, Gross   238,761 $ 252,422 $ 254,473
Loans held for sale, at lower of cost or fair value   1,402   971
Loans and Leases Receivable, Impaired, Commitment to Lend   259   241
Performing        
Loans and Leases Receivable Disclosure [Line Items]        
Troubled debt restructurings included in impaired loans   1,800   2,200
Credit Card Portfolio Segment [Member]        
Loans and Leases Receivable Disclosure [Line Items]        
Loans and Leases Receivable, Gross   110,685   114,762
Consumer Portfolio Segment [Member]        
Loans and Leases Receivable Disclosure [Line Items]        
Loans and Leases Receivable, Gross   59,329   75,078
Consumer Portfolio Segment [Member] | Performing        
Loans and Leases Receivable Disclosure [Line Items]        
Troubled debt restructurings included in impaired loans   1,100   1,300
Consumer Portfolio Segment [Member] | Automobile Loan [Member]        
Loans and Leases Receivable Disclosure [Line Items]        
Loans and Leases Receivable, Gross   56,422   53,991
Consumer Portfolio Segment [Member] | Home loan        
Loans and Leases Receivable Disclosure [Line Items]        
Transfer of Portfolio Loans and Leases to Held-for-sale $ 398      
Loans and Leases Receivable, Gross       17,633
Consumer Portfolio Segment [Member] | Retail Banking [Member]        
Loans and Leases Receivable Disclosure [Line Items]        
Loans and Leases Receivable, Gross   2,907   3,454
Commercial Banking        
Loans and Leases Receivable Disclosure [Line Items]        
Loans and Leases Receivable, Gross   68,747   64,575
Commercial Banking | Performing        
Loans and Leases Receivable Disclosure [Line Items]        
Troubled debt restructurings included in impaired loans   395   574
Other        
Loans and Leases Receivable Disclosure [Line Items]        
Loans and Leases Receivable, Gross   0   58
Federal Home Loan banks [Member]        
Loans and Leases Receivable Disclosure [Line Items]        
Loans Pledged as Collateral   16,500   27,300
Line of Credit Facility, Remaining Borrowing Capacity   20,400   21,000
Federal Reserve Discount Window [Member]        
Loans and Leases Receivable Disclosure [Line Items]        
Loans Pledged as Collateral   6,700   9,100
Line of Credit Facility, Remaining Borrowing Capacity   5,500   7,400
Interest Rate Type Concentration Risk | Home Loans Receivable | Consumer Portfolio Segment [Member] | Home loan        
Loans and Leases Receivable Disclosure [Line Items]        
Loans and Leases Receivable, Gross   0   17,633
Geographic Concentration Risk | Commercial Banking        
Loans and Leases Receivable Disclosure [Line Items]        
Loans and Leases Receivable, Gross   68,747   64,575
Geographic Concentration Risk | Loans Receivable | Consumer Portfolio Segment [Member] | Automobile Loan [Member]        
Loans and Leases Receivable Disclosure [Line Items]        
Loans and Leases Receivable, Gross   56,422   53,991
Geographic Concentration Risk | Loans Receivable | Consumer Portfolio Segment [Member] | Retail Banking [Member]        
Loans and Leases Receivable Disclosure [Line Items]        
Loans and Leases Receivable, Gross   $ 2,907   $ 3,454