DEBT (Outstanding Debt) (Details) $ / shares in Units, $ in Millions		1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Aug. 20, 2014 USD ($) Days $ / shares	May 31, 2013 USD ($) Days $ / shares	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Jun. 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			$ 7,771		$ 7,771					$ 8,787
Unamortized Debt Discount and Debt Issuance Cost			(85)		(85)					(138)
Carrying Value, Long-Term Debt			7,686		7,686					8,649
Description of Senior Notes
Payments for conversion of senior notes					0	$ (1,487)
0.35% Convertible Senior Notes due June 2020
Debt Instrument
Outstanding Principal Amount, Short-Term Debt			1,000		1,000
Carrying Value, Short-term debt			975		975
Outstanding Principal Amount, Long-Term Debt										1,000
Unamortized Debt Discount and Debt Issuance Cost			$ (25)		$ (25)					(39)
Carrying Value, Long-Term Debt										$ 961
Description of Senior Notes
Aggregate principal amount		$ 1,000
Interest rate on long-term debt		0.35%	0.35%		0.35%				0.35%	0.35%	0.35%
Debt financing costs paid								$ 1
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
Effective interest rate at debt origination or modification		3.13%
Debt discount related to convertible notes, net of tax																			$ 92
Debt discount related to convertible notes, before tax																			$ 154
Amortization of debt discount included in interest expense			$ 1		$ 2	1
0.9% Convertible Senior Notes due September 2021
Debt Instrument
Outstanding Principal Amount, Long-Term Debt			1,000		1,000					$ 1,000
Unamortized Debt Discount and Debt Issuance Cost			(50)		(50)					(61)
Carrying Value, Long-Term Debt			$ 950		$ 950					$ 939
Description of Senior Notes
Aggregate principal amount	$ 1,000
Interest rate on long-term debt	0.90%		0.90%		0.90%				0.90%	0.90%	0.90%
Debt financing costs paid							$ 11
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
Debt discount related to convertible notes, before tax							$ 143
0.8% (€1 Billion) Senior Notes due March 2022
Debt Instrument
Outstanding Principal Amount, Long-Term Debt			$ 1,139		$ 1,139					$ 1,143
Unamortized Debt Discount and Debt Issuance Cost			(4)		(4)					(5)
Carrying Value, Long-Term Debt			$ 1,135		$ 1,135					$ 1,138
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			$ 854		$ 854					$ 858
Unamortized Debt Discount and Debt Issuance Cost			(3)		(3)					(4)
Carrying Value, Long-Term Debt			$ 851		$ 851					$ 854
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		$ 500					$ 500
Unamortized Debt Discount and Debt Issuance Cost			(2)		(2)					(3)
Carrying Value, Long-Term Debt			$ 498		$ 498					$ 497
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			$ 1,139		$ 1,139					$ 1,143
Unamortized Debt Discount and Debt Issuance Cost			(10)		(10)					(10)
Carrying Value, Long-Term Debt			$ 1,129		$ 1,129					$ 1,133
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		$ 500					$ 500
Unamortized Debt Discount and Debt Issuance Cost			(3)		(3)					(3)
Carrying Value, Long-Term Debt			$ 497		$ 497					$ 497
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		$ 1,000					$ 1,000
Unamortized Debt Discount and Debt Issuance Cost			(6)		(6)					(6)
Carrying Value, Long-Term Debt			$ 994		$ 994					$ 994
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			$ 1,139		$ 1,139					$ 1,143
Unamortized Debt Discount and Debt Issuance Cost			(4)		(4)					(4)
Carrying Value, Long-Term Debt			$ 1,135		$ 1,135					$ 1,139
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		$ 500					$ 500
Unamortized Debt Discount and Debt Issuance Cost			(3)		(3)					(3)
Carrying Value, Long-Term Debt			$ 497		$ 497					$ 497
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
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)
Debt conversion, converted instrument, cash					773
Effective interest rate at debt origination or modification																				3.50%
Debt discount related to convertible notes, net of tax																				$ 81
Debt discount related to convertible notes, before tax																				$ 135
Convertible Debt
Description of Senior Notes
Interest expense related to debt			$ 16	$ 15	31	35
Coupon Interest expense			3	3	6	8
Amortization of debt discount included in interest expense			$ 12	$ 12	$ 24	$ 26
Debt, weighted average interest rate			3.20%	3.20%	3.20%	3.20%
Other Long-term Debt
Debt Instrument
Carrying Value, Long-Term Debt			$ 6,700		$ 6,700					$ 6,700
Description of Senior Notes
Interest expense related to debt			41	$ 43	83	$ 86
Coupon Interest expense			40	$ 41	80	$ 83
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
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
Level 2
Description of Senior Notes
Estimated market value of outstanding debt			$ 9,800		9,800					$ 9,300
Designated as Hedging Instrument | Minimum | Euro-Denominated Debt
Description of Senior Notes
Notional amount of nonderivative instruments					3,400
Designated as Hedging Instrument | Maximum | Euro-Denominated Debt
Description of Senior Notes
Notional amount of nonderivative instruments					$ 4,300