Accounting Pronouncements (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cost of sales	$ (4,691)	$ (5,183)	$ (4,629)
Selling, General and Administrative Expense	(483)	(546)	(496)
Research and Development Expense	(67)	(72)	(73)
Other (charges) gains, net	(203)	9	(59)
Operating profit (loss)	834	1,334	857
Non-operating pension and other postretirement employee benefit (expense) income	(20)	(62)	$ 44
Retained earnings	6,399	5,847
Operating lease, liability	210
Operating lease right-of-use assets	$ 203	$ 0
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease, liability				$ 240
Operating lease right-of-use assets				$ 223

Non-operating pension and other postretirement employee benefit (expense) income

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- Definition

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(a),(d))
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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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The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
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Amount of lessee's right to use underlying asset under operating lease.

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- Definition

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

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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