SUPPLEMENTAL FINANCIAL INFORMATION Other Non-Current Assets (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Other Non-Current Assets [Abstract]
Equity investments	$ 4,348	$ 4,076
Inventories	1,015	1,080
Operating leases	850	859
Pension and postretirement	216	208
Restricted cash - non current	199	338
Other	509	458
Other non-current assets	7,137	7,019
Restricted Cash	$ 339	$ 429