OTHER OPERATING EXPENSE (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Other Income and Expenses [Abstract]
Deposit insurance	$ 29	$ 34	$ 88	$ 102
Promotional expense	36	27	95	82
Settlements and operating losses	11	18	35	43
Other	55	54	160	178
Other operating expense	$ 131	$ 133	$ 378	$ 405