SUPPLEMENTAL FINANCIAL INFORMATION Other Non-Current Assets (Details) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Other Non-Current Assets [Abstract]
Equity investments	$ 4,166	$ 3,405
Inventories	1,163	1,373
Operating leases	718	704
Pension and postretirement	222	456
Restricted cash - non current	341	390
Other	286	276
Other non-current assets	6,896	$ 6,604
Restricted Cash	$ 425

Equity investments - non-current

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Other Non-Current Assets [Abstract]

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Inventories not expected to be converted to cash, sold or exchanged within the normal operating cycle.

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Amount of lessee's right to use underlying asset under operating lease.

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Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

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Amount of noncurrent assets classified as other.

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Amount of cash restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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