RETIREMENT BENEFITS - Defined Contribution Plans and Postemployment Plans (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Postemployment Retirement Benefits
Amortization of unrecognized:
Net actuarial loss	$ 0	$ 1
Total service-related benefit	0	1
Non-service-related expense	5	4
Total net (benefit) expense	5	5
U.S. \| Postretirement Benefit Plans
Defined Contribution Plans
Company's contributions for defined contribution plans	101	99
Amortization of unrecognized:
Total net (benefit) expense	0	2
Non-U.S. plans \| Postretirement Benefit Plans
Defined Contribution Plans
Company's contributions for defined contribution plans	76	68
Amortization of unrecognized:
Total net (benefit) expense	$ 9	$ 10

Represents the non-service related expense for defined benefit plans for the period.

No definition available.

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- Definition

Represents the service related expense for defined benefit plans for the period.

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- References

No definition available.

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- References

No definition available.

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- Definition

Amount of cost for defined contribution plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
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