STOCK-BASED COMPENSATION - Weighted-Average Assumptions and Fair Values Used of Performance Units Granted (Details) - Long-Term Incentive Performance Award - $ / shares	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Stockholders Equity Note [Line Items]
Risk-free interest rate	3.86%	4.45%
Expected volatility	28.39%	27.00%
Weighted-average fair value of options granted (in shares per share)	$ 94.54	$ 157.37
Share payout	98.13%	102.18%

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.

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+ Details

UNITED PARCEL SERVICE INC 10-Q