EXIT COSTS AND RESTRUCTURING RESERVES - Reserve Rollforward (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Restructuring Reserve [Roll Forward]
Beginning balance	$ 44	$ 26
Additions	28	124
Reversals	(2)	(10)
Utilization	(18)	(96)
Ending balance	52	44
Employee Severance | Salaries & Employee Benefits
Restructuring Reserve [Roll Forward]
Beginning balance	23	2
Additions	5	43
Reversals	(2)	(1)
Utilization	(5)	(21)
Ending balance	21	23
Facility Closing | Occupancy & Equipment
Restructuring Reserve [Roll Forward]
Beginning balance	18	24
Additions	17	24
Reversals	0	(5)
Utilization	(8)	(25)
Ending balance	27	18
Other Restructuring | Other
Restructuring Reserve [Roll Forward]
Beginning balance	3	0
Additions	6	57
Reversals	0	(4)
Utilization	(5)	(50)
Ending balance	$ 4	$ 3