EMPLOYEE BENEFIT PLANS - NET PENSION EXPENSE (DETAILS) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Qualified Defined Benefit [Member]
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	$ 11	$ 9
Interest cost	18	18
Expected return on assets	(27)	(23)
Amortization of prior service cost	0	0
Curtailment loss	0	0
Recognized actuarial loss	10	10
Net pension expense	12	14
Nonqualified Defined Benefit [Member]
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	0	0
Interest cost	1	1
Expected return on assets	0	0
Amortization of prior service cost	0	0
Curtailment loss	0	0
Recognized actuarial loss	0	0
Net pension expense	1	1
Postretirement Medical Benefits [Member]
Defined Benefit Plan, Net Periodic Benefit Cost [Abstract]
Service cost	1	1
Interest cost	1	2
Expected return on assets	0	0
Amortization of prior service cost	0	0
Curtailment loss	0	0
Recognized actuarial loss	0	0
Net pension expense	$ 2	$ 3