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DEBT - Other Long-term Debt (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Apr. 30, 2020
Debt Instrument [Line Items]
Aggregate principal amount	$ 11,201	$ 7,711
Euro-Denominated Debt \| Designated as Hedging Instrument \| Minimum
Debt Instrument [Line Items]
Carrying value of the portions of Euro-denominated debt, including accrued interest, designated as a net investment hedge	1,800	2,400
Euro-Denominated Debt \| Designated as Hedging Instrument \| Maximum
Debt Instrument [Line Items]
Carrying value of the portions of Euro-denominated debt, including accrued interest, designated as a net investment hedge	3,200	4,300
Senior Notes
Debt Instrument [Line Items]
Payments of debt issuance costs	19
Carrying value of long-term debt	$ 10,300	$ 6,700
Senior Notes \| 4.1% Senior Notes due April 2025
Debt Instrument [Line Items]
Stated interest rate	4.10%		4.10%
Aggregate principal amount	$ 1,000		$ 1,000
Senior Notes \| 4.5% Senior Notes due April 2027
Debt Instrument [Line Items]
Stated interest rate	4.50%		4.50%
Aggregate principal amount	$ 750		$ 750
Senior Notes \| 4.625% Senior Notes due April 2030
Debt Instrument [Line Items]
Stated interest rate	4.625%		4.625%
Aggregate principal amount	$ 1,500		$ 1,500