Segments - Geographic Information (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Segment Information
Revenue	$ 57,350	$ 55,179	$ 57,714
Plant and Other Property - Net	5,668	6,108	5,785
Operating right-of-use assets	$ 3,222	$ 3,566	$ 3,850
Revenue \| Major Client
Segment Information
Number of clients representing 10% or more of the company's total revenue	0	0	0
U.S. \| Revenue \| Geographic Information
Segment Information
Revenue	$ 22,893	$ 22,258	$ 23,389
U.S. \| Revenue \| Geographic Information \| Minimum
Segment Information
Concentration Risk, Percentage	10.00%	10.00%	10.00%
U.S. \| Plant and Other Property - Net \| Geographic Information
Segment Information
Plant and Other Property - Net	$ 3,375	$ 3,452	$ 3,513
U.S. \| Plant and Other Property - Net \| Geographic Information \| Minimum
Segment Information
Concentration Risk, Percentage	10.00%	10.00%	10.00%
U.S. \| Operating Right-Of-Use Assets - Net \| Geographic Information
Segment Information
Operating right-of-use assets	$ 1,148	$ 1,165	$ 1,305
U.S. \| Operating Right-Of-Use Assets - Net \| Geographic Information \| Minimum
Segment Information
Concentration Risk, Percentage	10.00%	10.00%	10.00%
Japan \| Revenue \| Geographic Information
Segment Information
Revenue	$ 5,648	$ 5,680	$ 5,755
Japan \| Revenue \| Geographic Information \| Minimum
Segment Information
Concentration Risk, Percentage	10.00%	10.00%	10.00%
Japan \| Operating Right-Of-Use Assets - Net \| Geographic Information
Segment Information
Operating right-of-use assets	$ 398	$ 532	$ 599
Japan \| Operating Right-Of-Use Assets - Net \| Geographic Information \| Minimum
Segment Information
Concentration Risk, Percentage	10.00%	10.00%	10.00%
Non-United States \| Plant and Other Property - Net \| Geographic Information
Segment Information
Plant and Other Property - Net	$ 2,293	$ 2,656	$ 2,273
Non-United States \| Plant and Other Property - Net \| Geographic Information \| Minimum
Segment Information
Concentration Risk, Percentage	10.00%	10.00%	10.00%
Other Countries \| Revenue \| Geographic Information
Segment Information
Revenue	$ 28,810	$ 27,241	$ 28,570
Other Countries \| Revenue \| Geographic Information \| Minimum
Segment Information
Concentration Risk, Percentage	10.00%	10.00%	10.00%
Other Countries \| Operating Right-Of-Use Assets - Net \| Geographic Information
Segment Information
Operating right-of-use assets	$ 1,676	$ 1,870	$ 1,947
Other Countries \| Operating Right-Of-Use Assets - Net \| Geographic Information \| Minimum
Segment Information
Concentration Risk, Percentage	10.00%	10.00%	10.00%

The number of customers that individually represent 10 percent or more of the company's total revenue.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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

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Amount, after accumulated depreciation and excluding lessor's underlying asset for which right to use has been conveyed to lessee under operating lease, of physical asset used in normal conduct of business to create and distribute product and service.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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