PENSION AND OTHER POSTRETIREMENT BENEFITS - Estimated Future Benefit Payments (Details) $ in Millions	Dec. 31, 2021 USD ($)
Defined Benefit Plan Disclosure [Line Items]
2022	$ 593
2023	598
2024	598
2025	599
2026	596
2027 — 2031	2,884
Pension
Defined Benefit Plan Disclosure [Line Items]
2022	563
2023	569
2024	571
2025	573
2026	572
2027 — 2031	2,780
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
2022	30
2023	29
2024	27
2025	26
2026	24
2027 — 2031	$ 104
Expected future benefit percentage of gross payments, excluding subsidiaries	10.00%

Defined Benefit Plan, Expected Future Benefit Percentage of Gross Payments, Excluding Subsidiaries

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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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- Definition

Amount of benefit for defined benefit plan expected to be paid in five fiscal years 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
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

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- Definition

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

+ References

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- Definition

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.

+ References

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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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