MARKETABLE SECURITIES AND NON-CURRENT INVESTMENTS - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024
Gain (Loss) on Securities [Line Items]
Equity method investments	$ 251		$ 304
Impairment charge on equity metho investment		$ 19
Carrying value of equity method investment sold	31
Equity securities without readily determinable fair value, amount	48		$ 42
UPS Digital \| Held-for-sale
Gain (Loss) on Securities [Line Items]
Consideration transferred, equity securities	$ 23

Disposal Group, Including Discontinued Operation, Consideration, Equity Securities

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- Definition

Amount of other-than-temporary decline in value that has been recognized against investment accounted for under equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of the entity's equity method investment which has been sold.

+ References

No definition available.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of investment in equity security without readily determinable fair value.

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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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