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Contingencies and Environmental Liabilities - Patent Litigation - Narrative (Details) $ in Millions	1 Months Ended		12 Months Ended
	Jan. 31, 2018 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2018 USD ($) legalmatter	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Gain Contingencies [Line Items]
Litigation settlement, gain (loss)			$ 0	$ 0	$ (625)
Number of patents allegedly infringed upon | legalmatter			2
Patent litigation
Gain Contingencies [Line Items]
Litigation settlement, gain (loss)	$ 115
Settlement awarded to company		$ 2,540

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Number of entity's patents that another entity has allegedly infringed.

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Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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Amount awarded from other party in judgment or settlement of litigation.

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