Number of shares purchased.

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- Definition

Liquidation value of preferred shares.

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No definition available.

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- Definition

Payments to acquire an investment in preferred stock and common stock of an equity method investee.

+ References

No definition available.

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- Definition

The ratio of shares of common stock of an investee issued per share of common stock of a merging company.

+ References

No definition available.

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- Definition

Exercise price of the warrants.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column A

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(2))
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- Definition

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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-Publisher FASB
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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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The profit or loss on sales of previously unissued stock by equity investees made to investors outside the consolidated group that is not reported as operating income. Represents the difference in the parent company's carrying amount of the equity interest in the subsidiary or equity investee immediately before and after the transaction.

+ References

No definition available.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Amount of dividend income on nonoperating securities.

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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The cash inflow associated with maturities (principal being due), prepayments and calls (requests of early payments) on securities not classified as either held-to-maturity securities or trading securities which are classified as available-for-sale securities.

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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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No definition available.

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Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

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No definition available.

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Investments in The Kraft Heinz Company - Narrative (Detail) - USD ($) $ / shares in Units, $ in Millions					1 Months Ended	12 Months Ended
	Dec. 31, 2017	Jun. 07, 2016	Jul. 02, 2015	Jul. 01, 2015	Jun. 30, 2013	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Equity Method Investments [Line Items]
Purchase of common stock								$ 5,258
Equity method earnings on common stock						$ 2,938	$ 923	(122)
Berkshire Hathaway Inc. (Parent) [Member]
Schedule of Equity Method Investments [Line Items]
Non-cash pre-tax holding gain								6,838
Investment in common stock	$ 17,635					17,635	15,345
Equity method earnings on common stock						2,938	923	(122)
Berkshire Hathaway Inc. (Parent) [Member] \| Kraft Heinz (previously Heinz Holding) [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage				52.50%	50.00%
Equity method investment ownership percentage after transactions	26.70%		26.80%
Investment in common stock	$ 17,635					17,635	15,345
Equity method earnings on common stock						2,938
Common stock dividends received						$ 797	952
3G Capital (venture partner) [Member] \| Kraft Heinz (previously Heinz Holding) [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage					50.00%
Equity method investment ownership percentage after transactions			24.20%
Common Stock, Cumulative Compounding Preferred Stock and Warrants [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Kraft Heinz (previously Heinz Holding) [Member]
Schedule of Equity Method Investments [Line Items]
Purchase of preferred stock, common stock and warrants					$ 12,250
Common Stock [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Kraft Heinz (previously Heinz Holding) [Member]
Schedule of Equity Method Investments [Line Items]
Number of shares acquired					425,000,000
Number of common shares that can be purchased					46,000,000
Exercise price for warrants, per share					$ 0.01
Purchase of common stock				$ 5,258
Non-cash pre-tax holding gain								$ 6,838
Common Stock [Member] \| 3G Capital (venture partner) [Member] \| Kraft Heinz (previously Heinz Holding) [Member]
Schedule of Equity Method Investments [Line Items]
Number of shares acquired					425,000,000
Purchase of common stock				$ 4,740	$ 4,250
Cumulative Compounding Preferred Stock [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Kraft Heinz (previously Heinz Holding) [Member]
Schedule of Equity Method Investments [Line Items]
Investment in preferred stock, liquidation value					$ 8,000
Dividends earned on preferred stock							$ 180
Redemption of preferred stock		$ 8,320
Kraft [Member] \| Kraft Heinz (previously Heinz Holding) [Member]
Schedule of Equity Method Investments [Line Items]
Ratio of common stock shares issued per Kraft common stock share			1