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Amount of distribution received from equity method investee for return of investment.

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Amount of distribution received from equity method investee for return of investment that is non recurring.

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Percentage of investment acquired by members or limited partners of limited liability company (LLC).

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Number of places retail locations located.

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Percentage of obligation to indemnify for any losses incurred under surety policy by counterparty.

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Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.

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Amount of distribution received from equity method investee for return on investment, classified as operating activities. Excludes distribution for return of investment, classified as investing activities.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Balance held at close of period in number of shares.

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Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Represents the number of stores.

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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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Equity method investments - Narrative (Detail)	3 Months Ended			9 Months Ended
Equity method investments - Narrative (Detail)	Sep. 30, 2021 USD ($) Store Location shares	Mar. 31, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) Store Location shares	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Schedule of Equity Method Investments [Line Items]
Equity method earnings (losses)	$ 377,000,000		$ 290,000,000	$ 775,000,000	$ 333,000,000
Pilot Travel Centers LLC [Member]
Schedule of Equity Method Investments [Line Items]
Number of retail \| Store	1,000			1,000
Pilot Travel Centers LLC [Member] \| U.S. States [Member]
Schedule of Equity Method Investments [Line Items]
Number of places retail locations located \| Location	44			44
Pilot Travel Centers LLC [Member] \| Canadian Provinces [Member]
Schedule of Equity Method Investments [Line Items]
Number of places retail locations located \| Location	6			6
Pilot Travel Centers LLC [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage				38.60%
Pilot Travel Centers LLC [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Agreement to Acquire Additional Interest in 2023 [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of additional interest to be acquired				41.40%
Haslam Family [Member] \| Pilot Travel Centers LLC [Member]
Schedule of Equity Method Investments [Line Items]
Majority ownership percentage				50.10%
Haslam Family [Member] \| Pilot Travel Centers LLC [Member] \| Agreement to Acquire Additional Interest in 2023 [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage				20.00%
Third Party [Member] \| Pilot Travel Centers LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage				11.30%
The Kraft Heinz Company [Member]
Schedule of Equity Method Investments [Line Items]
Number of shares owned \| shares	325,442,152			325,442,152
Equity method investment ownership percentage	26.50%			26.50%
Equity method investments, fair value	$ 12,000,000,000.0			$ 12,000,000,000.0		$ 11,300,000,000
Equity method investments, carrying value	13,300,000,000			13,300,000,000		13,300,000,000
Equity method earnings (losses)	$ 194,000,000		$ 159,000,000	337,000,000	(180,000,000)
Impairment charges on equity investment					850,000,000
Common stock dividends received				$ 391,000,000	391,000,000
Difference between carrying value and fair value percentage	10.00%			10.00%
Berkadia Commercial Mortgage LLC, Pilot Travel Centers LLC, and Electric Transmission Texas, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investments, carrying value	$ 3,400,000,000			$ 3,400,000,000		$ 4,000,000,000.0
Equity method earnings (losses)				438,000,000	$ 513,000,000
Equity method investment distributions from other investees				$ 1,000,000,000.0
Pilot Travel Centers LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment non-recurring distribution		$ 849,000,000
Berkadia Commercial Mortgage LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage	50.00%			50.00%
Commercial paper outstanding	$ 1,470,000,000			$ 1,470,000,000
Berkadia Commercial Mortgage LLC [Member] \| Commercial Paper [Member]
Schedule of Equity Method Investments [Line Items]
Maximum outstanding balance of commercial paper borrowings	$ 1,500,000,000			$ 1,500,000,000
Berkadia Commercial Mortgage LLC [Member] \| Jefferies Financial Group Inc. [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage	50.00%			50.00%
Berkadia Commercial Mortgage LLC [Member] \| Jefferies Financial Group Inc. [Member] \| Commercial Paper [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of obligation to indemnify for any losses incurred under surety policy				50.00%
Electric Transmission Texas, LLC [Member] \| Berkshire Hathaway Energy Company Subsidiary [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage	50.00%			50.00%
Electric Transmission Texas, LLC [Member] \| American Electric Power [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage	50.00%			50.00%