Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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

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Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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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 cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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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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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Amount of acquisition of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Asset Acquisitions, Dispositions and Other (Details) - USD ($)	1 Months Ended				3 Months Ended
	Sep. 30, 2018	Jul. 31, 2018	Mar. 31, 2018	Jan. 31, 2018	Dec. 31, 2018
4.2% senior notes due 2048
Asset Acquisitions, Dispositions and Other
Debt instrument issued			$ 1,000,000,000.0
Debt instrument interest rate stated percentage			4.20%
Net proceeds of debt			$ 985,000,000
1.50% senior notes due 2018
Asset Acquisitions, Dispositions and Other
Debt instrument interest rate stated percentage			1.50%
Repayment of debt			$ 500,000,000
2018 Credit Facility
Asset Acquisitions, Dispositions and Other
Debt instrument issued				$ 3,000,000,000.0
Credit facility term				5 years
Previously leased power and steam cogeneration facility
Asset Acquisitions, Dispositions and Other
Acquisition cost		$ 443,000,000
Disposed of by sale \| Non-core Midstream assets
Asset Acquisitions, Dispositions and Other
Divestiture consideration	$ 2,600,000,000		150,000,000
Proceeds received for divested assets	2,400,000,000
Pre-tax net gain from divestiture	$ 902,000,000		$ 43,000,000
Scenario, Forecast \| Previously leased power and steam cogeneration facility
Asset Acquisitions, Dispositions and Other
Payment to acquire previously leased facility					$ 60,000,000