Quarterly report pursuant to Section 13 or 15(d)

FAIR VALUES OF ASSETS AND LIABILITIES - Fair Value Option-Changs in Fair Value (Details)

v3.8.0.1
FAIR VALUES OF ASSETS AND LIABILITIES - Fair Value Option-Changs in Fair Value (Details) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Fair Value, Measurements, Recurring    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Net gains (losses) from fair value changes $ 2 $ 9
Consumer loans    
Fair Value, Option, Quantitative Disclosures [Line Items]    
Net gains (losses) from fair value changes $ 0 $ 0