Significant Business Acquisitions - Lubrizol (Detail) (The Lubrizol Corporation [Member], USD $) In Millions	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 16, 2011
The Lubrizol Corporation [Member]
Liabilities, noncontrolling interests and net assets acquired:
Accounts payable and other liabilities			$ 1,684
Notes payable and other borrowings			1,607
Income taxes, principally deferred			1,669
Noncontrolling interests			78
Total liabilities and noncontrolling interests			5,038
Net assets acquired			8,704
Total liabilities, noncontrolling interests and net assets acquired			13,742
Assets:
Cash and cash equivalents			893
Inventory			1,598
Property, plant and equipment			2,303
Intangible assets			3,710
Goodwill			4,210
Other			1,028
Total assets			13,742
Total revenues	110,205	104,115
Net earnings attributable to Berkshire Hathaway shareholders	$ 7,608	$ 8,818
Earnings per equivalent Class A common share attributable to Berkshire Hathaway shareholders	$ 4,612	$ 5,405

The pro forma net income (loss) for the period attributable to the parent as if the business combination or combinations had been completed at the beginning of a period.

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The amount of acquisition cost of a business combination allocated to liabilities assumed and noncontrolling interest in the acquiree.

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The amount of acquisition cost allocated to noncontrolling interest in the acquiree.

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Amount of acquisition cost of a business combination allocated to other assets not separately disclosed in the balance sheet.

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The amount of acquisition cost of a business combination allocated to assets acquired.

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The total purchase price of the acquired entity. This includes cash paid to equity interest holders of the acquired entity, fair value of debt and equity securities issued to equity holders of the acquired entity, and transaction costs paid to third parties to consummate the acquisition.

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The amount of cash and cash equivalents acquired in a business combination.

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The amount of acquisition cost of a business combination allocated to inventory, including finished goods, work-in-process, and raw materials.

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Amount of goodwill arising from a business combination, which is the excess of the cost of the acquired entity over the amounts assigned to assets acquired and liabilities assumed.

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The amount of acquisition cost of a business combination allocated to notes payables and long-term debt assumed from the acquired entity.

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The amount of acquisition cost of a business combination allocated to property, plant and equipment to be used in ongoing operations.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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