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DEBT (Long-Term Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2020	May 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Debt Instrument [Line Items]
Total long-term debt	$ 4,015		$ 4,770
Debt issuance costs	(28)		(26)
Less: current portion of long-term debt	2		804
Total long-term debt, net of current portion	4,013		3,966
Other
Debt Instrument [Line Items]
Other	27		34
Senior Notes \| 4.75% Senior Notes due January 2020
Debt Instrument [Line Items]
Total long-term debt	$ 0		500
Debt instrument, interest rate	4.75%
Senior Notes \| 2.50% Senior Notes due March 2020
Debt Instrument [Line Items]
Total long-term debt	$ 0		300
Debt instrument, interest rate	2.50%
Senior Notes \| 4.70% Senior Notes due April 2021
Debt Instrument [Line Items]
Total long-term debt	$ 0		554
Debt instrument, interest rate	4.70%
Senior Notes \| 4.25% Senior Notes due April 2024
Debt Instrument [Line Items]
Total long-term debt	$ 316		308
Debt instrument, interest rate	4.25%
Senior Notes \| 3.50% Senior Notes due March 2025
Debt Instrument [Line Items]
Total long-term debt	$ 622		593
Debt instrument, interest rate	3.50%
Senior Notes \| 3.45% Senior Notes due June 2026
Debt Instrument [Line Items]
Total long-term debt	$ 512		490
Debt instrument, interest rate	3.45%
Senior Notes \| 4.20% Senior Notes due June 2029
Debt Instrument [Line Items]
Total long-term debt	$ 499		499
Debt instrument, interest rate	4.20%			4.20%
Senior Notes \| 2.95% Senior Notes due June 2030
Debt Instrument [Line Items]
Total long-term debt	$ 798		$ 798
Debt instrument, interest rate	2.95%		2.95%
Senior Notes \| 2.80% Senior Notes due June 2031
Debt Instrument [Line Items]
Total long-term debt	$ 549		$ 0
Debt instrument, interest rate	2.80%	2.80%
Senior Notes \| 6.95% Senior Notes due July 2037
Debt Instrument [Line Items]
Total long-term debt	$ 175		175
Debt instrument, interest rate	6.95%
Senior Notes \| 5.75% Senior Notes due January 2040
Debt Instrument [Line Items]
Total long-term debt	$ 245		245
Debt instrument, interest rate	5.75%
Senior Notes \| 4.70% Senior Notes due March 2045
Debt Instrument [Line Items]
Total long-term debt	$ 300		$ 300
Debt instrument, interest rate	4.70%