Approximate annual revenues reported by the acquiree company.

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

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The recovery percentage of the entity's surety bond claim losses that its joint venture partner is obligated to pay.

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Number of persons employed by the Entity

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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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Balance held at close of period in number of shares.

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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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Equity Method Investments - Narrative (Detail) $ in Millions		3 Months Ended
	Oct. 03, 2017 USD ($) Employee Location	Mar. 31, 2018 USD ($) shares	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)
Schedule of Equity Method Investments [Line Items]
Equity method earnings		$ 401	$ 281
Berkadia Commercial Mortgage LLC, Pilot Travel Centers LLC, d/b/a Pilot Flying J, and Electric Transmission Texas [Member]
Schedule of Equity Method Investments [Line Items]
Equity method earnings		$ 136	42
Berkadia Commercial Mortgage (investee) [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage		50.00%
Other Assets [Member] \| Berkadia Commercial Mortgage LLC, Pilot Travel Centers LLC, d/b/a Pilot Flying J, and Electric Transmission Texas [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investments		$ 3,500		$ 3,400
Berkshire Hathaway Inc. (Parent) [Member] \| Kraft Heinz (previously Heinz Holding) [Member]
Schedule of Equity Method Investments [Line Items]
Number of shares owned \| shares		325,442,152
Equity method investment ownership percentage		26.70%
Equity method investments		$ 17,687		$ 17,635
Equity method earnings		265	239
Common stock dividends received		$ 203	$ 195
Leucadia National Corporation (venture partner) [Member] \| Berkadia Commercial Mortgage (investee) [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage		50.00%
American Electric Power [Member] \| Electric Transmission Texas [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage		50.00%
Commercial Paper [Member] \| Berkadia Commercial Mortgage (investee) [Member]
Schedule of Equity Method Investments [Line Items]
Maximum outstanding balance of commercial paper borrowings		$ 1,500
Insurance Group [Member] \| Leucadia National Corporation (venture partner) [Member] \| Berkadia Commercial Mortgage (investee) [Member]
Schedule of Equity Method Investments [Line Items]
Reimbursement rate from joint venture partner of Company's surety bond claim losses		50.00%
Pilot Travel Centers LLC, d/b/a Pilot Flying J [Member]
Schedule of Equity Method Investments [Line Items]
Number of locations \| Location	750
Annual revenues	$ 20,000
Pilot Travel Centers LLC, d/b/a Pilot Flying J [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	38.60%
Pilot Travel Centers LLC, d/b/a Pilot Flying J [Member] \| Haslam Family [Member]
Schedule of Equity Method Investments [Line Items]
Majority ownership percentage	50.10%
Pilot Travel Centers LLC, d/b/a Pilot Flying J [Member] \| Third Party [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	11.30%
Berkshire Hathaway Energy Company Subsidiary [Member] \| Electric Transmission Texas [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage		50.00%
Minimum [Member] \| Pilot Travel Centers LLC, d/b/a Pilot Flying J [Member]
Schedule of Equity Method Investments [Line Items]
Number of team members \| Employee	27,000
Agreement to Acquire Additional Interest in 2023 [Member] \| Pilot Travel Centers LLC, d/b/a Pilot Flying J [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of additional interest to be acquired	41.40%
Agreement to Acquire Additional Interest in 2023 [Member] \| Pilot Travel Centers LLC, d/b/a Pilot Flying J [Member] \| Haslam Family [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	20.00%