Disposal Group, Including Discontinued Operation, Area of Land Sold

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- Definition

Disposal Group, Including Discontinued Operation, Fee Surface Area Sold

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- Definition

Disposal Group, Including Discontinued Operation, Liabilities Settled Related to Future Royalties

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

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

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- Definition

Amount classified as deferred tax liabilities attributable to disposal group held for sale or disposed of.

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- Definition

Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of, expected to be disposed of after one year or the normal operating cycle, if longer.

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Amount, before tax, of (gain) loss recognized for the (reversal of write-down) write-down to fair value, less cost to sell, of a disposal group. Excludes discontinued operations.

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- Definition

Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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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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Amount classified as liabilities attributable to disposal group held for sale or disposed of.

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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Divestitures and Other Transactions - Narrative (Details) a in Millions, $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Sep. 30, 2020 USD ($)	Aug. 31, 2020 USD ($) a	Dec. 31, 2019 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment and related charges			$ 8,600
Subsequent Event \| Variable rate bonds due February 2021
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Maturity of notes	2 years
Ghana Assets
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment and related charges		$ 1,400		$ 1,400
Discontinued Operations, Disposed of by Sale \| Wyoming, Colorado, and Utah Assets
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Area of land sold (acres) \| a					4.5
Fee surface sold (acres) \| a					1.0
Agreement consideration					$ 1,330
Discontinued Operations, Disposed of by Sale \| Wyoming, Colorado, and Utah Assets \| Subsequent Event
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Net proceeds from sale	$ 1,000
Liabilities satisfied associated with future royalties	329
Loss on sale of assets	431
Discontinued Operations, Disposed of by Sale \| Columbia Assets
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss associated with remeasuring assets to fair value		356
Discontinued Operations, Disposed of by Sale \| Columbia Assets \| Subsequent Event
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Property, plant and equipment, net	$ 587
Discontinued Operations, Disposed of by Sale \| Ghana Assets
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment and related charges			1,400
Discontinued Operations, Held-for-sale \| Wyoming, Colorado, and Utah Assets
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Property, plant and equipment, net		1,400		1,400
Total Liabilities		338		338
Discontinued Operations, Held-for-sale \| Ghana Assets
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Property, plant and equipment, net		1,400		1,400		$ 3,600
Deferred income taxes presented in liabilities held for sale		$ 750		$ 750
Impairment and related charges			$ 2,200