DEBT (Outstanding Debt) (Details)		1 Months Ended		3 Months Ended		9 Months Ended		12 Months Ended
	Aug. 20, 2014 USD ($) Days $ / shares	Mar. 31, 2018 USD ($)	May 31, 2013 USD ($) Days $ / shares	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Sep. 30, 2019 EUR (€)	Dec. 31, 2018 USD ($)	Dec. 31, 2018 EUR (€)	Aug. 15, 2017	Mar. 10, 2017	May 23, 2016	Nov. 25, 2015	Mar. 13, 2015	Mar. 03, 2015	Sep. 23, 2014	Jun. 30, 2013 USD ($)	Mar. 31, 2012 USD ($) $ / shares
Debt Instrument
Outstanding Principal Amount, Long-Term Debt				$ 7,588,000,000		$ 7,588,000,000					$ 8,787,000,000
Unamortized Debt Discount and Debt Issuance Cost				(76,000,000)		(76,000,000)					(138,000,000)
Long-term Debt				7,512,000,000		7,512,000,000					8,649,000,000
Description of Senior Notes
Payments for conversion of senior notes						0	$ 1,487,000,000
0.35% Convertible Senior Notes due June 2020
Debt Instrument
Outstanding Principal Amount, Short-Term Debt				1,000,000,000		1,000,000,000
Outstanding Principal Amount, Long-Term Debt											1,000,000,000
Unamortized Debt Discount and Debt Issuance Cost				(18,000,000)		(18,000,000)					(39,000,000)
Carrying Value, Short-term debt				$ 982,000,000		$ 982,000,000
Long-term Debt											$ 961,000,000
Description of Senior Notes
Aggregate principal amount			$ 1,000,000,000.0
Interest rate on long-term debt			0.35%	0.35%		0.35%				0.35%	0.35%	0.35%
Debt financing costs paid									$ 1,000,000
Convertible debt conversion price (in dollars per share) | $ / shares			$ 1,315.10
Ratio of closing share price to conversion price as a condition for conversion of the convertible notes, minimum			150.00%
Unamortized debt discount			$ 20,000,000
Effective interest rate at debt origination or modification			3.13%
Debt discount related to convertible notes, net of tax																				$ 92,000,000
Debt discount related to convertible notes, before tax																				$ 154,000,000
Amortization of debt discount included in interest expense					$ 1,000,000	$ 2,000,000	2,000,000
0.9% Convertible Senior Notes due September 2021
Debt Instrument
Outstanding Principal Amount, Long-Term Debt				$ 1,000,000,000		1,000,000,000					$ 1,000,000,000
Unamortized Debt Discount and Debt Issuance Cost				(44,000,000)		(44,000,000)					(61,000,000)
Long-term Debt				$ 956,000,000		$ 956,000,000					$ 939,000,000
Description of Senior Notes
Aggregate principal amount	$ 1,000,000,000.0
Interest rate on long-term debt	0.90%			0.90%		0.90%				0.90%	0.90%	0.90%
Debt financing costs paid								$ 11,000,000
Convertible debt conversion price (in dollars per share) | $ / shares	$ 2,055.50
Ratio of closing share price to conversion price as a condition for conversion of the convertible notes, minimum	150.00%
Effective interest rate at debt origination or modification	3.18%
Debt discount related to convertible notes, net of tax								83,000,000
Debt discount related to convertible notes, before tax								$ 143,000,000
0.8% (€1 Billion) Senior Notes due March 2022
Debt Instrument
Outstanding Principal Amount, Long-Term Debt				$ 1,090,000,000		$ 1,090,000,000					$ 1,143,000,000
Unamortized Debt Discount and Debt Issuance Cost				(4,000,000)		(4,000,000)					(5,000,000)
Long-term Debt				$ 1,086,000,000		$ 1,086,000,000					$ 1,138,000,000
Description of Senior Notes
Aggregate principal amount | €										€ 1,000,000,000		€ 1,000,000,000
Interest rate on long-term debt				0.80%		0.80%				0.80%	0.80%	0.80%
Effective interest rate at debt origination or modification														0.84%
2.15% (€750 Million) Senior Notes due November 2022
Debt Instrument
Outstanding Principal Amount, Long-Term Debt				$ 818,000,000		$ 818,000,000					$ 858,000,000
Unamortized Debt Discount and Debt Issuance Cost				(3,000,000)		(3,000,000)					(4,000,000)
Long-term Debt				$ 815,000,000		$ 815,000,000					$ 854,000,000
Description of Senior Notes
Aggregate principal amount | €										€ 750,000,000		€ 750,000,000
Interest rate on long-term debt				2.15%		2.15%				2.15%	2.15%	2.15%
Effective interest rate at debt origination or modification																2.20%
2.75% Senior Notes due March 2023
Debt Instrument
Outstanding Principal Amount, Long-Term Debt				$ 500,000,000		$ 500,000,000					$ 500,000,000
Unamortized Debt Discount and Debt Issuance Cost				(2,000,000)		(2,000,000)					(3,000,000)
Long-term Debt				$ 498,000,000		$ 498,000,000					$ 497,000,000
Description of Senior Notes
Interest rate on long-term debt				2.75%		2.75%				2.75%	2.75%	2.75%
Effective interest rate at debt origination or modification													2.78%
2.375% (€1 Billion) Senior Notes due September 2024
Debt Instrument
Outstanding Principal Amount, Long-Term Debt				$ 1,090,000,000		$ 1,090,000,000					$ 1,143,000,000
Unamortized Debt Discount and Debt Issuance Cost				(8,000,000)		(8,000,000)					(10,000,000)
Long-term Debt				$ 1,082,000,000		$ 1,082,000,000					$ 1,133,000,000
Description of Senior Notes
Aggregate principal amount | €										€ 1,000,000,000		€ 1,000,000,000
Interest rate on long-term debt				2.375%		2.375%				2.375%	2.375%	2.375%
Effective interest rate at debt origination or modification																			2.48%
3.65% Senior Notes due March 2025
Debt Instrument
Outstanding Principal Amount, Long-Term Debt				$ 500,000,000		$ 500,000,000					$ 500,000,000
Unamortized Debt Discount and Debt Issuance Cost				(3,000,000)		(3,000,000)					(3,000,000)
Long-term Debt				$ 497,000,000		$ 497,000,000					$ 497,000,000
Description of Senior Notes
Interest rate on long-term debt				3.65%		3.65%				3.65%	3.65%	3.65%
Effective interest rate at debt origination or modification																	3.68%
3.6% Senior Notes due June 2026
Debt Instrument
Outstanding Principal Amount, Long-Term Debt				$ 1,000,000,000		$ 1,000,000,000					$ 1,000,000,000
Unamortized Debt Discount and Debt Issuance Cost				(5,000,000)		(5,000,000)					(6,000,000)
Long-term Debt				$ 995,000,000		$ 995,000,000					$ 994,000,000
Description of Senior Notes
Interest rate on long-term debt				3.60%		3.60%				3.60%	3.60%	3.60%
Effective interest rate at debt origination or modification															3.62%
1.8% (€1 Billion) Senior Notes due March 2027
Debt Instrument
Outstanding Principal Amount, Long-Term Debt				$ 1,090,000,000		$ 1,090,000,000					$ 1,143,000,000
Unamortized Debt Discount and Debt Issuance Cost				(4,000,000)		(4,000,000)					(4,000,000)
Long-term Debt				$ 1,086,000,000		$ 1,086,000,000					$ 1,139,000,000
Description of Senior Notes
Aggregate principal amount | €										€ 1,000,000,000		€ 1,000,000,000
Interest rate on long-term debt				1.80%		1.80%				1.80%	1.80%	1.80%
Effective interest rate at debt origination or modification																		1.80%
3.55% Senior Notes due March 2028
Debt Instrument
Outstanding Principal Amount, Long-Term Debt				$ 500,000,000		$ 500,000,000					$ 500,000,000
Unamortized Debt Discount and Debt Issuance Cost				(3,000,000)		(3,000,000)					(3,000,000)
Long-term Debt				$ 497,000,000		$ 497,000,000					$ 497,000,000
Description of Senior Notes
Interest rate on long-term debt				3.55%		3.55%				3.55%	3.55%	3.55%
Effective interest rate at debt origination or modification													3.56%
1.0% Convertible Senior Notes due March 2018
Description of Senior Notes
Aggregate principal amount																					$ 1,000,000,000.0
Interest rate on long-term debt																					1.00%
Convertible debt conversion price (in dollars per share) | $ / shares																					$ 944.61
Payments for conversion of senior notes		$ 714,000,000
Debt conversion, converted instrument, cash		$ 773,000,000
Effective interest rate at debt origination or modification																					3.50%
Debt discount related to convertible notes, net of tax																					$ 81,000,000
Debt discount related to convertible notes, before tax																					$ 135,000,000
Convertible Debt
Description of Senior Notes
Interest expense related to debt				$ 16,000,000	15,000,000	$ 47,000,000	50,000,000
Amortization of debt discount included in interest expense				12,000,000	12,000,000	36,000,000	38,000,000
Coupon Interest expense				$ 3,000,000	$ 3,000,000	$ 9,000,000	$ 11,000,000
Debt, weighted average interest rate				3.20%	3.20%	3.20%	3.20%
Other Long-term Debt
Debt Instrument
Long-term Debt				$ 6,600,000,000		$ 6,600,000,000					$ 6,700,000,000
Description of Senior Notes
Interest expense related to debt				42,000,000	$ 42,000,000	125,000,000	$ 128,000,000
Coupon Interest expense				40,000,000	$ 40,000,000	120,000,000	$ 123,000,000
Minimum | 0.35% Convertible Senior Notes due June 2020
Description of Senior Notes
Minimum and Maximum consecutive days the closing sales price of common stock must exceed a specified percentage of conversion price to trigger conversion feature of note (in days) | Days			20
Additional payment to debt holder, settled In shares, aggregate value			$ 0
Minimum | 0.9% Convertible Senior Notes due September 2021
Description of Senior Notes
Minimum and Maximum consecutive days the closing sales price of common stock must exceed a specified percentage of conversion price to trigger conversion feature of note (in days) | Days	20
Additional payment to debt holder, settled In shares, aggregate value	$ 0
Maximum | 0.35% Convertible Senior Notes due June 2020
Description of Senior Notes
Minimum and Maximum consecutive days the closing sales price of common stock must exceed a specified percentage of conversion price to trigger conversion feature of note (in days) | Days			30
Additional payment to debt holder, settled In shares, aggregate value			$ 397,000,000
Maximum | 0.9% Convertible Senior Notes due September 2021
Description of Senior Notes
Minimum and Maximum consecutive days the closing sales price of common stock must exceed a specified percentage of conversion price to trigger conversion feature of note (in days) | Days	30
Additional payment to debt holder, settled In shares, aggregate value	$ 375,000,000
Level 2
Description of Senior Notes
Estimated market value of outstanding debt				$ 9,700,000,000		9,700,000,000					$ 9,300,000,000
Designated as Hedging Instrument | Minimum | Euro-Denominated Debt
Description of Senior Notes
Notional amount of nonderivative instruments						2,400,000,000
Designated as Hedging Instrument | Maximum | Euro-Denominated Debt
Description of Senior Notes
Notional amount of nonderivative instruments						$ 4,300,000,000