1.0.0.3trueConsolidated Statements of Earnings (USD $)In Millions, except Share datafalse1$falsefalseSharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170false2$falsefalseSharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170false3$falsefalseSharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso4217022us-gaaptruenadurationstringNo definition available.falsefalsefalsefalsefalsetruefalsefalsefalse1falsefalse00falsefalse2falsefalse00falsefalse3falsefalse00falsefalseNo definition available.false122us-gaap_Revenuesus-gaaptruecreditdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1truetrue112493000000112493falsefalse2truetrue107786000000107786falsefalse3truetrue118245000000118245falsefalseNo definition available.No authoritative reference available.true132us-gaaptruenadurationstringNo definition available.falsefalsefalsefalsefalsetruefalsefalsefalse1falsefalse00falsefalse2falsefalse00falsefalse3falsefalse00falsefalseNo definition available.false222us-gaap_CostsAndExpensesus-gaaptruedebitdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue100941000000100941falsefalse2falsetrue100212000000100212falsefalse3falsetrue9808400000098084falsefalseNo definition available.No authoritative reference available.true232us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestmentsus-gaaptruecreditdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue1155200000011552falsefalse2falsetrue75740000007574falsefalse3falsetrue2016100000020161falsefalseNo definition available.No authoritative reference available.true242us-gaap_IncomeTaxExpenseBenefitus-gaaptruedebitdurationmonetaryNo definition 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unrealized gain (loss) included in earnings for the period as a result of...falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue251000000251falsefalse2falsetrue11660000001166falsefalse3falsetrue54050000005405falsefalseThis item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain or loss of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain or loss which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains or losses realized during the period from the sale of investments accounted for under the cost method of accounting.No authoritative reference available.false1042brka_OtherThanTemporaryImpairmentLossesInvestmentsPortionRecognizedInEarningsNetbrkafalsedebitdurationmonetaryThe amount of other than temporary impairment losses on equity securities, other than temporary impairment related to credit...falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue-3155000000-3155falsefalse2falsetrue-1813000000-1813falsefalse3falsefalse00falsefalseThe amount of other than temporary impairment losses on equity securities, other than temporary impairment related to credit losses on debt securities, and other than temporary impairment losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes other than temporary impairment losses recognized during the period on investments accounted for under the cost method of accounting.No authoritative reference available.false1052us-gaap_Revenuesus-gaaptruecreditdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue9278000000092780falsefalse2falsetrue9569800000095698falsefalse3falsetrue100410000000100410falsefalseNo definition available.No authoritative reference available.true1062us-gaaptruenadurationstringNo definition available.falsefalsefalsefalsefalsetruefalsefalsefalse1falsefalse00falsefalse2falsefalse00falsefalse3falsefalse00falsefalseNo definition available.false1072us-gaap_IncurredClaimsPropertyCasualtyAndLiabilityus-gaaptruedebitdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue1825100000018251falsefalse2falsetrue1625900000016259falsefalse3falsetrue2101000000021010falsefalseNo definition available.No 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available.false1362us-gaap_Revenuesus-gaaptruecreditdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue1144300000011443falsefalse2falsetrue1397100000013971falsefalse3falsetrue1262800000012628falsefalseNo definition available.No authoritative reference available.true1372us-gaaptruenadurationstringNo definition available.falsefalsefalsefalsefalsetruefalsefalsefalse1falsefalse00falsefalse2falsefalse00falsefalse3falsefalse00falsefalseNo definition available.false1432us-gaap_UtilitiesOperatingExpenseus-gaaptruedebitdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue87390000008739falsefalse2falsetrue98400000009840falsefalse3falsetrue96960000009696falsefalseNo definition available.No authoritative reference available.false1442us-gaap_InterestExpenseus-gaaptruedebitdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue11760000001176falsefalse2falsetrue11680000001168falsefalse3falsetrue11580000001158falsefalseNo definition available.No authoritative reference available.false1462us-gaap_CostsAndExpensesus-gaaptruedebitdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue99150000009915falsefalse2falsetrue1100800000011008falsefalse3falsetrue1085400000010854falsefalseNo definition available.No authoritative reference available.true1560natruenananaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalse1falsefalse00falsefalse2falsefalse00falsefalse3falsefalse00falsefalseNo definition available.No authoritative reference available.false1572us-gaaptruenadurationstringNo definition available.falsefalsefalsefalsefalsetruefalsefalsefalse1falsefalse00falsefalse2falsefalse00falsefalse3falsefalse00falsefalseNo definition available.false1602us-gaap_InvestmentIncomeInterestAndDividendus-gaaptruecreditdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue18860000001886falsefalse2falsetrue17900000001790falsefalse3falsetrue17170000001717falsefalseNo definition available.No authoritative reference available.false1612brka_GainLossOnInvestmentsExcludingOtherThanTemporaryImpairmentsbrkafalsecreditdurationmonetaryThis item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of...falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue6700000067falsefalse2falsetrue70000007falsefalse3falsetrue193000000193falsefalseThis item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain or loss of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain or loss which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains or losses realized during the period from the sale of investments accounted for under the cost method of accounting.No authoritative reference available.false1632us-gaap_GainLossOnDerivativeInstrumentsNetPretaxus-gaaptruecreditdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue36240000003624falsefalse2falsetrue-6821000000-6821falsefalse3falsetrue-89000000-89falsefalseNo definition available.No authoritative reference available.false1652us-gaap_RevenueOtherFinancialServicesus-gaaptruecreditdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue26930000002693falsefalse2falsetrue31410000003141falsefalse3falsetrue33860000003386falsefalseNo definition available.No authoritative reference available.false1672us-gaap_Revenuesus-gaaptruecreditdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue82700000008270falsefalse2falsetrue-1883000000-1883falsefalse3falsetrue52070000005207falsefalseNo definition available.No authoritative reference available.true1682us-gaaptruenadurationstringNo definition available.falsefalsefalsefalsefalsetruefalsefalsefalse1falsefalse00falsefalse2falsefalse00falsefalse3falsefalse00falsefalseNo definition available.false1752us-gaap_InterestExpenseus-gaaptruedebitdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue686000000686falsefalse2falsetrue639000000639falsefalse3falsetrue588000000588falsefalseNo definition available.No authoritative reference available.false1762us-gaap_OtherFinancialServicesCostsus-gaaptruedebitdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1falsetrue31210000003121falsefalse2falsetrue35210000003521falsefalse3falsetrue34940000003494falsefalseNo definition available.No authoritative reference available.false1772us-gaap_CostsAndExpensesus-gaaptruedebitdurationmonetaryNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalse1truetrue38070000003807falsefalse2truetrue41600000004160falsefalse3truetrue40820000004082falsefalseNo definition available.No authoritative reference available.true1Average shares outstanding include average Class A common shares and average Class B common shares determined on an equivalent Class A common stock basis. Net earnings per share attributable to Berkshire Hathaway shareholders shown above represents net earnings per equivalent Class A common share. Net earnings per Class B common share is equal to one-fifteen-hundredth (1/1,500) of such amount or $3.46 per share for 2009, $2.15 per share for 2008 and $5.70 per share for 2007 after giving effect to the 50-for-1 Class B stock split that became effective on January 21, 2010. See Note 19.false353falseMillionsNoRoundingUnKnownfalsetrue