RETIREMENT BENEFITS - Contributions (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
U.S. | Pension Plans
Defined Benefit Plan, Expected Future Employer Contributions [Abstract]
Company contributions for the six months ended June 30	$ 26	$ 28
Company contributions made or expected to be made during the remainder of the year	29	528
U.S. | Postretirement Benefit Plans
Defined Benefit Plan, Expected Future Employer Contributions [Abstract]
Company contributions for the six months ended June 30	19	6
Company contributions made or expected to be made during the remainder of the year	0	0
Non-U.S. plans | Pension Plans
Defined Benefit Plan, Expected Future Employer Contributions [Abstract]
Company contributions for the six months ended June 30	70	58
Company contributions made or expected to be made during the remainder of the year	70	68
Non-U.S. plans | Postretirement Benefit Plans
Defined Benefit Plan, Expected Future Employer Contributions [Abstract]
Company contributions for the six months ended June 30	4	3
Company contributions made or expected to be made during the remainder of the year	$ 4	$ 6