RETIREMENT BENEFITS - Sensitivities of Certain Key Assumptions (Details) - Pension Plans - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans
Effect of one-percentage-point increase in discount rates	$ 22	$ 27	$ 35
Effect of one-percentage-point decrease in discount rates	(26)	(34)	(49)
Effect of one-percentage-point increase on benefits earned and interest cost for U.S. postretirement plans	(112)	(123)	(124)
Effect of one-percentage-point decrease on benefits earned and interest cost for U.S. postretirement plans	112	123	124
Non-U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans
Effect of one-percentage-point increase in discount rates	(12)	(5)	(4)
Effect of one-percentage-point decrease in discount rates	20	15	25
Effect of one-percentage-point increase on benefits earned and interest cost for U.S. postretirement plans	(54)	(60)	(70)
Effect of one-percentage-point decrease on benefits earned and interest cost for U.S. postretirement plans	$ 54	$ 60	$ 70

The effect of a one-percentage-point decrease in the discount rates on pension expenses.

No definition available.

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- Definition

The effect of a one-percentage-point decrease in the expected rates of return on pension expenses.

+ References

No definition available.

+ Details

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- Definition

The effect of a one-percentage-point increase in the discount rates on pension expenses.

+ References

No definition available.

+ Details

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- Definition

The effect of a one-percentage-point increase in the expected rates of return on pension expenses.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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