Amounts in Paragraphs - Summary of Significant Accounting Policies (Details 1) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 07, 2020
Summary of Significant Accounting Policies (Amounts in paragraphs)
Research and development expenses	$ 764	$ 1,100	$ 953
Research and Development as a Percent of Sales	2.50%	2.90%	2.80%
Cash surrender value of life insurance		$ 419	$ 380
Stock plans, vesting period		3 years
Disposal Group, Including Discontinued Operation, Consideration					$ 3,400
Revenue from Sale of Equipment to a Customer		$ 444
Proceeds from Sale of Equipment to a Customer		205	0	$ 0
Non-Cash Proceeds from sale of equipment to a customer		239
Capital Expenditures Incurred but Not yet Paid		$ 72	$ 166	$ 185

Cash flow from Sale of Equipment to a Customer

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The non-cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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Research and Development as a Percent of Sales

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Revenue from Sale of Equipment to a Customer

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Future cash outflow to pay for purchases of fixed assets that have occurred.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

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Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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