RETIREMENT BENEFITS PLANS - Estimated Pension and Other Postretirement Benefit Payments (Details) $ in Millions	Dec. 31, 2020 USD ($)
Pension plans \| United States
Defined Benefit Plans and Other Postretirement Benefit Plans
2021	$ 406
2022	298
2023	289
2024	280
2025	272
2026 - 2030	1,218
Pension plans \| Foreign Plan
Defined Benefit Plans and Other Postretirement Benefit Plans
2021	100
2022	101
2023	105
2024	107
2025	112
2026 - 2030	613
Other postretirement benefits plans
Defined Benefit Plans and Other Postretirement Benefit Plans
2021	28
Medicare prescription drug subsidy 2021	(1)
2022	31
Medicare prescription drug subsidy 2022	0
2023	27
Medicare prescription drug subsidy 2023	0
2024	26
Medicare prescription drug subsidy 2024	0
2025	24
Medicare prescription drug subsidy 2025	0
2026 - 2030	107
Medicare prescription drug subsidy 2026 - 2030	$ (1)

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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Amount of prescription drug subsidy receipt expected after fifth fiscal year following current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
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Amount of prescription drug subsidy receipt expected in next fiscal year following current fiscal year.

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Amount of prescription drug subsidy receipt expected in fifth fiscal year following current fiscal year.

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Amount of prescription drug subsidy receipt expected in fourth fiscal year following current fiscal year.

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Amount of prescription drug subsidy receipt expected in third fiscal year following current fiscal year.

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Amount of prescription drug subsidy receipt expected in second fiscal year following current fiscal year.

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