FAIR VALUE MEASUREMENTS - Summary of Recurring Measured Fair Values (Details) - USD ($) $ in Millions		Jun. 30, 2020	Dec. 31, 2019
Liabilities, Fair Value Disclosure [Abstract]
Long Term Debt, Including Debt Due within one year, Fair Value		$ (19,893)	$ (17,251)
Recurring | Level 2
Assets, Fair Value Disclosure [Abstract]
Cash equivalents and restricted cash equivalents	[1]	2,555	454
Total assets at fair value		2,562	470
Liabilities, Fair Value Disclosure [Abstract]
Long Term Debt, Including Debt Due within one year, Fair Value	[2]	19,893	17,251
Total liabilities at fair value		19,920	17,268
Recurring | Level 2 | Foreign currency
Assets, Fair Value Disclosure [Abstract]
Foreign Currency Contracts	[3]	7	16
Liabilities, Fair Value Disclosure [Abstract]
Foreign Currency Contracts	[3]	$ 27	$ 17

[1] Treasury bills, time deposits, and money market funds included in "Cash and cash equivalents" and money market funds included in "Other current assets" in the interim Condensed Consolidated Balance Sheets and held at amortized cost, which approximates fair value.

[2] Fair value is based on quoted market prices for the same or similar issues, or on current rates offered to the company for debt of the same remaining maturities and terms.

[3] See Note 19 for the classification of derivatives in the interim Condensed Consolidated Balance Sheets.