RETIREMENT-RELATED BENEFITS - Contributions, Defined Benefit Plans (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Non-U.S. Defined Benefit and Multi-Employer Plans
Pension Contributions
Estimated cash contributions to the defined benefit plans in next fiscal year	$ 500
Non-US Pension Plans
Pension Contributions
Contributions by employer to defined benefit plans	464	$ 474
Contributions by employer - Cash	169	474
Contributions by employer - Noncash	295
Multi-employer Plans - Non U.S. Plans
Pension Contributions
Cash contribution by employer to non-U.S. multi-employer plans	$ 43	40
U.S. Defined Benefit Plans
Pension Contributions
Period over which company may smooth the change in value of pension assets under revised funding requirements in Worker, Retiree and Employer Recovery Act of 2008	24 months
Nonpension Postretirement Plans
Pension Contributions
Employer contributions, excluding the Medicare-related subsidy	$ 305	408
Contributions by employer - Cash	80	328
Contributions by employer - Noncash	$ 225	$ 80

Cash contributions made by the employer during the period to a defined benefit plan.

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- Definition

The employer's contributions, excluding the Medicare-related subsidy, towards the defined benefit plan.

+ References

No definition available.

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- Definition

Noncash contributions made by the employer during the period to a defined benefit plan. These contributions may be in the form of securities.

+ References

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The period of months over which the company may smooth the change in value of pension plan assets under revised funding requirements in Worker, Retiree and Employer Recovery Act of 2008

+ References

No definition available.

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- Definition

Amount of contributions made by the employer to defined benefit plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

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- Definition

Amount of contributions made to multiemployer plans by the employer. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

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