DEBT - Schedule of Outstanding Debt (Details) € in Millions, $ in Millions	Jun. 30, 2021 USD ($)	Jun. 30, 2021 EUR (€)	Mar. 31, 2021 EUR (€)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 EUR (€)	Apr. 30, 2020 USD ($)	Aug. 31, 2017	Mar. 31, 2017	May 31, 2016	Nov. 30, 2015	Mar. 31, 2015	Sep. 30, 2014	Aug. 31, 2014 USD ($)
Current Liabilities:
Carrying Value	$ 2,180			$ 985
Long-term debt:
Carrying Value	9,986			11,029
Total long-term debt
Long-term debt:
Outstanding Principal  Amount	10,139			11,201
Unamortized Debt Discount and Debt Issuance Cost	(153)			(172)
Carrying Value	9,986			11,029
Total short-term debt
Current Liabilities:
Carrying Value	2,180
Long-term debt:
Outstanding Principal  Amount	2,186
Unamortized Debt Discount and Debt Issuance Cost	(6)
0.9% Convertible Senior Notes due September 2021 | Convertible Debt
Long-term debt:
Aggregate principal amount													$ 1,000
Stated interest rate													0.90%
0.9% Convertible Senior Notes due September 2021 | Convertible Debt
Current Liabilities:
Carrying Value	995			985
Long-term debt:
Outstanding Principal  Amount	1,000			1,000
Unamortized Debt Discount and Debt Issuance Cost	$ (5)			$ (15)
Stated interest rate	0.90%	0.90%		0.90%	0.90%
0.8% (€1 billion) Senior Notes due March 2022 | Senior Notes
Long-term debt:
Outstanding Principal  Amount				$ 1,223
Unamortized Debt Discount and Debt Issuance Cost				(1)
Carrying Value				$ 1,222
Aggregate principal amount | €					€ 1,000
Stated interest rate				0.80%	0.80%			0.80%
0.8% (€1 billion) Senior Notes due March 2022 | Senior Notes
Current Liabilities:
Carrying Value	$ 1,185
Long-term debt:
Outstanding Principal  Amount	1,186
Unamortized Debt Discount and Debt Issuance Cost	$ (1)
Aggregate principal amount | €		€ 1,000
Stated interest rate	0.80%	0.80%
2.15% (€750 million) Senior Notes due November 2022 | Senior Notes
Long-term debt:
Outstanding Principal  Amount	$ 889			$ 919
Unamortized Debt Discount and Debt Issuance Cost	(1)			(4)
Carrying Value	$ 888			$ 915
Aggregate principal amount | €		€ 750			€ 750
Stated interest rate	2.15%	2.15%		2.15%	2.15%					2.15%
2.75% Senior Notes due March 2023 | Senior Notes
Long-term debt:
Outstanding Principal  Amount	$ 500			$ 500
Unamortized Debt Discount and Debt Issuance Cost	(1)			(1)
Carrying Value	$ 499			$ 499
Stated interest rate	2.75%	2.75%		2.75%	2.75%		2.75%
2.375% (€1 billion) Senior Notes due September 2024 | Senior Notes
Long-term debt:
Outstanding Principal  Amount	$ 1,186			$ 1,223
Unamortized Debt Discount and Debt Issuance Cost	(6)			(7)
Carrying Value	$ 1,180			$ 1,216
Aggregate principal amount | €		€ 1,000			€ 1,000
Stated interest rate	2.375%	2.375%		2.375%	2.375%							2.375%
3.65% Senior Notes due March 2025 | Senior Notes
Long-term debt:
Outstanding Principal  Amount	$ 500			$ 500
Unamortized Debt Discount and Debt Issuance Cost	(2)			(2)
Carrying Value	$ 498			$ 498
Stated interest rate	3.65%	3.65%		3.65%	3.65%						3.65%
0.1% (€950 million) Senior Notes due March 2025 | Senior Notes
Long-term debt:
Outstanding Principal  Amount	$ 1,126		€ 950
Unamortized Debt Discount and Debt Issuance Cost	(5)
Carrying Value	$ 1,121
Aggregate principal amount | €		€ 950
Stated interest rate	0.10%	0.10%	0.10%
4.1% Senior Notes due April 2025 | Senior Notes
Long-term debt:
Outstanding Principal  Amount				$ 1,000
Unamortized Debt Discount and Debt Issuance Cost				(5)
Carrying Value				$ 995
Stated interest rate				4.10%	4.10%
0.75% Convertible Senior Notes due May 2025 | Convertible Debt
Long-term debt:
Outstanding Principal  Amount	$ 863			$ 863
Unamortized Debt Discount and Debt Issuance Cost	(113)			(128)
Carrying Value	$ 750			$ 735
Aggregate principal amount						$ 863
Stated interest rate	0.75%	0.75%		0.75%	0.75%	0.75%
3.6% Senior Notes due June 2026 | Senior Notes
Long-term debt:
Outstanding Principal  Amount	$ 1,000			$ 1,000
Unamortized Debt Discount and Debt Issuance Cost	(4)			(4)
Carrying Value	$ 996			$ 996
Stated interest rate	3.60%	3.60%		3.60%	3.60%				3.60%
1.8% (€1 billion) Senior Notes due March 2027 | Senior Notes
Long-term debt:
Outstanding Principal  Amount	$ 1,186			$ 1,223
Unamortized Debt Discount and Debt Issuance Cost	(3)			(2)
Carrying Value	$ 1,183			$ 1,221
Aggregate principal amount | €		€ 1,000			€ 1,000
Stated interest rate	1.80%	1.80%		1.80%	1.80%						1.80%
4.5% Senior Notes due April 2027 | Senior Notes
Long-term debt:
Outstanding Principal  Amount				$ 750
Unamortized Debt Discount and Debt Issuance Cost				(5)
Carrying Value				$ 745
Stated interest rate				4.50%	4.50%
3.55% Senior Notes due March 2028 | Senior Notes
Long-term debt:
Outstanding Principal  Amount	$ 500			$ 500
Unamortized Debt Discount and Debt Issuance Cost	(2)			(2)
Carrying Value	$ 498			$ 498
Stated interest rate	3.55%	3.55%		3.55%	3.55%		3.55%
0.5% (€750 million) Senior Notes due March 2028 | Senior Notes
Long-term debt:
Outstanding Principal  Amount	$ 889		€ 750
Unamortized Debt Discount and Debt Issuance Cost	(5)
Carrying Value	$ 884
Aggregate principal amount | €		€ 750
Stated interest rate	0.50%	0.50%	0.50%
4.625% Senior Notes due April 2030 | Senior Notes
Long-term debt:
Outstanding Principal  Amount	$ 1,500			$ 1,500
Unamortized Debt Discount and Debt Issuance Cost	(11)			(11)
Carrying Value	$ 1,489			$ 1,489
Stated interest rate	4.625%	4.625%		4.625%	4.625%	4.625%