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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).

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The number of businesses acquired by the entity during the period.

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Aggregate cash proceeds received from a combination of transactions in which noncurrent assets are sold, which may include the sale of a business, an investment in an affiliate (including an equity method investee), property, plant and equipment and intangible assets. Excludes sales of trading, available-for-sale, and held-to-maturity securities.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Acquisitions, Divestitures and Deconsolidation (Details) $ / shares in Units, $ in Millions		3 Months Ended								12 Months Ended
	Jun. 29, 2018 USD ($) $ / shares	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($) Acquisition	Dec. 31, 2018 USD ($) Acquisition
Acquisitions, Divestitures and Deconsolidation [Abstract]
Deconsolidation loss, after tax				$ (957)
Purchase of Boardwalk Pipelines common units												$ (1,718)
Revenues		$ 3,709	$ 3,465	$ 2,310	$ 3,099	$ 3,876	$ 3,675	$ 3,623	$ 3,757	$ 12,583	$ 14,931	14,066
Goodwill recognized		785				767				785	767	665
Additional Paid-in Capital [Member]
Acquisitions, Divestitures and Deconsolidation [Abstract]
Purchase of Boardwalk Pipelines common units												658
AOCI [Member]
Acquisitions, Divestitures and Deconsolidation [Abstract]
Purchase of Boardwalk Pipelines common units												(29)
Diamond Offshore [Member]
Acquisitions, Divestitures and Deconsolidation [Abstract]
Deconsolidation loss										(1,200)
Deconsolidation loss, after tax										(957)
Boardwalk Pipelines [Member]
Acquisitions, Divestitures and Deconsolidation [Abstract]
Purchase price per unit (in dollars per share) \| $ / shares	$ 12.06
Payments for acquisition	$ 1,500
Increase to deferred income tax liabilities	213
Boardwalk Pipelines [Member] \| Additional Paid-in Capital [Member]
Acquisitions, Divestitures and Deconsolidation [Abstract]
Purchase of Boardwalk Pipelines common units	658
Boardwalk Pipelines [Member] \| AOCI [Member]
Acquisitions, Divestitures and Deconsolidation [Abstract]
Purchase of Boardwalk Pipelines common units	$ (29)
Loews Hotels & Co [Member]
Acquisitions, Divestitures and Deconsolidation [Abstract]
Proceeds from sale of assets										57	118	40
Altium Packaging [Member] \| Packaging Manufacturer [Member]
Acquisitions, Divestitures and Deconsolidation [Abstract]
Payments for acquisition										60
Goodwill recognized		17								17
Altium Packaging [Member] \| Packaging Manufacturer [Member] \| Customer Relationships [Member]
Acquisitions, Divestitures and Deconsolidation [Abstract]
Intangible assets recognized		$ 35								35
Altium Packaging [Member] \| Plastic Packaging Manufacturers [Member]
Acquisitions, Divestitures and Deconsolidation [Abstract]
Payments for acquisition											$ 260
Number of businesses acquired \| Acquisition											3
Revenues										$ 135	$ 76
Goodwill recognized						99					99
Debt financing proceeds											250
Altium Packaging [Member] \| Plastic Packaging Manufacturers [Member] \| Customer Relationships [Member]
Acquisitions, Divestitures and Deconsolidation [Abstract]
Intangible assets recognized						$ 87					$ 87
Altium Packaging [Member] \| Plastic Packaging Manufacturers [Member]
Acquisitions, Divestitures and Deconsolidation [Abstract]
Payments for acquisition												$ 40
Number of businesses acquired \| Acquisition												3
Goodwill recognized												$ 10
Intangible assets recognized												$ 15