PENSION PLANS AND OTHER POSTRETIREMENT BENEFITS (Pension Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan, Cost Recognized	$ 16	$ 15	$ 13
Pension contributions	2	2	158
Change in Accounting Estimate, Estimated Amount of Change in the Next Fiscal Year from the Adoption of the Spot Rate Approach	37
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Projected Benefit Obligation	3,993	4,345
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Accumulated Benefit Obligation	3,960	4,302
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Fair Value of Plan Assets	3,173	3,543
Other Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	0	$ 0	$ 0
Defined Benefit Plan, Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation	$ 2
Discount rate - benefit obligations	4.08%	3.75%	4.40%
Discount rate - net periodic costs	3.75%	4.40%	3.65%
Defined Benefit Plan, Actuarial Gain (Loss)	$ 19	$ (13)
Defined Benefit Plan, Benefit Obligation	276	270	$ 302
Defined Benefit Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Fair Value of Plan Assets	3,173	$ 3,543	$ 3,586
Defined Benefit Plans, Estimated Future Employer Contributions in Next Fiscal Year	$ 52
Discount rate - benefit obligations	4.26%	3.90%	4.75%
Rate of increase in future compensation levels - benefit obligations	4.50%	4.50%	4.50%
Discount rate - net periodic costs	3.90%	4.75%	3.85%
Rate of increase in future compensation levels - net periodic costs	4.50%	4.50%	4.50%
Expected long-term rate of return on plan assets - net periodic costs	6.80%	6.80%	6.90%
Defined Benefit Plan, Actuarial Gain (Loss)	$ (178)	$ 531
Defined Benefit Plan, Benefit Obligation	$ 3,993	4,345	$ 3,995
2014 SOA Mortality Change [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Actuarial Gain (Loss)		$ 139
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Support, Bond Indices	60
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate Support, Bond Indices	90