PENSION PLANS AND OTHER POSTRETIREMENT BENEFITS (Net Periodic Benefit Cost and Other Changes in Plan Assets and Benefit Obligations Recognized in Other Comprehensive Income for All Significant Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 44	$ 30	$ 31
Defined Benefit Plan, Interest Cost	164	183	165
Expected return on plan assets	(226)	(232)	(232)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	(1)	6	7
Amortization of net (gain) loss	87	66	88
Defined Benefit Plan, Net Periodic Benefit Cost	68	53	59
Net (gain) loss	34	450	(283)
Prior Service Cost (Credit)	4	(38)	0
Other Comprehensive (Income) Loss, Amortization Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Prior Service Cost (Credit), before Tax	(1)	6	7
Amortization of net (gain) loss	(87)	(66)	(88)
Total recognized in other comprehensive (income) loss	(48)	340	(378)
Total recognized in net periodic benefit cost and other comprehensive (income) loss	20	393	(319)
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	2
Defined Benefit Plan, Interest Cost	10	13	14
Expected return on plan assets	0	0	0
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	(1)	0	(1)
Amortization of net (gain) loss	(10)	(10)	0
Defined Benefit Plan, Net Periodic Benefit Cost	0	4	15
Net (gain) loss	19	(12)	(102)
Prior Service Cost (Credit)	0	0	0
Other Comprehensive (Income) Loss, Amortization Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Prior Service Cost (Credit), before Tax	(1)	0	(1)
Amortization of net (gain) loss	10	10	0
Total recognized in other comprehensive (income) loss	30	(2)	(101)
Total recognized in net periodic benefit cost and other comprehensive (income) loss	$ 30	$ 2	$ (86)