FAIR VALUE MEASUREMENTS - Book Values and Fair Values of Financial Instruments (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Book values
Fair Value And Carrying Value By Balance Sheet Grouping [Line Items]
Short-term debt	$ 200	$ 301
Current maturities of long-term debt and finance lease obligations	209	210
Long-term debt and finance lease obligations	16,765	17,149
Fair values
Fair Value And Carrying Value By Balance Sheet Grouping [Line Items]
Short-term debt	200	301
Current maturities of long-term debt and finance lease obligations	209	212
Long-term debt and finance lease obligations	$ 16,221	$ 17,568