Supplemental Financial Information - Other Non-Current Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Voluntary Separation Program	$ 190	$ 233
Postretirement obligation	334	330
Other deferred compensation	302	369
Other	270	292
Other noncurrent liabilities	1,096	1,224
Unusual or Infrequent Item, or Both [Line Items]
Taxes receivable	$ 219	699
CARES Act
Unusual or Infrequent Item, or Both [Line Items]
Taxes receivable		$ 472

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