Annual report pursuant to Section 13 and 15(d)

OTHER COMPREHENSIVE INCOME - Reclassifications (Details)

v3.8.0.1
OTHER COMPREHENSIVE INCOME - Reclassifications (Details) - USD ($)
$ in Millions
 9 Months Ended 12 Months Ended
Sep. 30, 2017
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Interest income—held-to-maturity securities—taxable   $ 193 $ 138 $ 87
Gain (Loss) on Sale of Securities, Net   0 2 3
Noninterest income—net gains (losses) on sale of securities, OTTI $ (4) (4) (2) (2)
Interest income - loans and leases   2,838 2,178 1,760
Noninterest income - other income   185 157 167
Noninterest expense—personnel costs   1,524 1,349 $ 1,122
Net of tax   (28) 44  
Unrealized gains (losses) on cash flow hedging derivatives        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Net of tax   (1) 0  
Unrealized gains (losses) for pension and other post-retirement obligations        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Net of tax   (10) (25)  
Reclassification out of Accumulated Other Comprehensive Income | Unrealized gains and (losses) on securities        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Interest income—held-to-maturity securities—taxable   (8) 91  
Gain (Loss) on Sale of Securities, Net   (14) 18  
Noninterest income—net gains (losses) on sale of securities, OTTI   (4) (2)  
Total before tax   (26) 107  
Tax (expense) benefit   9 (38)  
Net of tax   (17) 69  
Reclassification out of Accumulated Other Comprehensive Income | Unrealized gains (losses) on cash flow hedging derivatives        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Total before tax   (1) 0  
Tax (expense) benefit   0 0  
Net of tax   (1) 0  
Reclassification out of Accumulated Other Comprehensive Income | Unrealized gains (losses) on cash flow hedging derivatives | Interest Rate Contract        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Interest income - loans and leases   (1) 0  
Noninterest income - other income   0 0  
Reclassification out of Accumulated Other Comprehensive Income | Unrealized gains (losses) for pension and other post-retirement obligations        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Total before tax   (16) (38)  
Tax (expense) benefit   6 13  
Net of tax   (10) (25)  
Reclassification out of Accumulated Other Comprehensive Income | Actuarial gains (losses)        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Noninterest expense—personnel costs   (18) (40)  
Reclassification out of Accumulated Other Comprehensive Income | Net periodic benefit costs        
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]        
Noninterest expense—personnel costs   $ 2 $ 2