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DEBT (Long-Term Debt) (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
DEBT (Long-Term Debt) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018	Mar. 31, 2019
Debt Instrument [Line Items]
Total long-term debt	$ 3,993	$ 3,893
Debt issuance costs	(19)	(17)
Less: Current portion of long-term debt	805	464
Total long-term debt, net of current portion	3,188	3,429
Secured Receivables Credit Facility
Debt Instrument [Line Items]
Total long-term debt	0	$ 160
Credit facility borrowing rate		3.39%
2.70% Senior Notes due April 2019
Debt Instrument [Line Items]
Total long-term debt	0	$ 300
Debt instrument, interest rate		2.70%
Debt instrument, maturity date		Apr. 01, 2019
4.75% Senior Notes due January 2020
Debt Instrument [Line Items]
Total long-term debt	$ 501	$ 507
Debt instrument, interest rate	4.75%
Debt instrument, maturity date	Jan. 30, 2020
2.50% Senior Notes due March 2020
Debt Instrument [Line Items]
Total long-term debt	$ 300	300
Debt instrument, interest rate	2.50%
Debt instrument, maturity date	Mar. 30, 2020
4.70% Senior Notes due April 2021
Debt Instrument [Line Items]
Total long-term debt	$ 554	557
Debt instrument, interest rate	4.70%
Debt instrument, maturity date	Apr. 01, 2021
4.25% Senior Notes due April 2024
Debt Instrument [Line Items]
Total long-term debt	$ 310	299
Debt instrument, interest rate	4.25%
Debt instrument, maturity date	Apr. 01, 2024
3.50% Senior Notes due March 2025
Debt Instrument [Line Items]
Total long-term debt	$ 600	562
Debt instrument, interest rate	3.50%
Debt instrument, maturity date	Mar. 30, 2025
3.45% Senior Notes due June 2026
Debt Instrument [Line Items]
Total long-term debt	$ 494	469
Debt instrument, interest rate	3.45%
Debt instrument, maturity date	Jun. 30, 2026
4.20% Senior Notes due June 2029
Debt Instrument [Line Items]
Total long-term debt	$ 499	0
Debt instrument, interest rate	4.20%		4.20%
Debt instrument, maturity date	Jun. 30, 2029
6.95% Senior Notes due July 2037
Debt Instrument [Line Items]
Total long-term debt	$ 175	175
Debt instrument, interest rate	6.95%
Debt instrument, maturity date	Jul. 01, 2037
5.75% Senior Notes due January 2040
Debt Instrument [Line Items]
Total long-term debt	$ 244	244
Debt instrument, interest rate	5.75%
Debt instrument, maturity date	Jan. 30, 2040
4.70% Senior Notes due March 2045
Debt Instrument [Line Items]
Total long-term debt	$ 300	300
Debt instrument, interest rate	4.70%
Debt instrument, maturity date	Mar. 30, 2045
Other
Debt Instrument [Line Items]
Other	$ 35	$ 37