EMPLOYEE BENEFITS - Schedule of Net Periodic (Income) Cost (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 2	$ 3
Interest cost	36	36
Expected return on plan assets	(55)	(53)
Amortization of actuarial loss	12	7
Net periodic pension (income) cost	(5)	(7)
Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	2	3
Interest cost	33	33
Expected return on plan assets	(55)	(53)
Amortization of actuarial loss	10	6
Net periodic pension (income) cost	(10)	(11)
Non-Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0
Interest cost	3	3
Expected return on plan assets	0	0
Amortization of actuarial loss	2	1
Net periodic pension (income) cost	$ 5	$ 4