Interim Consolidated Financial Statements (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained earnings	$ 11,086	$ 10,689
Trade accounts receivable, net	$ 3,419	$ 3,087

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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