Investments in The Kraft Heinz Company - Narrative (Detail)				1 Months Ended		3 Months Ended	6 Months Ended
	Jul. 02, 2015 shares	Jul. 01, 2015 USD ($) shares	Jun. 07, 2013 USD ($) shares	Jun. 30, 2015 $ / shares shares	Mar. 31, 2015 $ / shares	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)
Kraft Heinz (previously Heinz Holding) [Member] | Berkshire Hathaway (Parent) [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage			50.00%	52.50%			52.50%
Kraft Heinz (previously Heinz Holding) [Member] | Berkshire Hathaway (Parent) [Member] | Common Stock [Member]
Schedule of Equity Method Investments [Line Items]
Number of shares acquired			425,000,000
Number of shares acquired upon exercise of warrants				46,000,000
Exercise price for warrants, per share | $ / shares				$ 0.01
Kraft Heinz (previously Heinz Holding) [Member] | Berkshire Hathaway (Parent) [Member] | Cumulative Compounding Preferred Stock [Member]
Schedule of Equity Method Investments [Line Items]
Investment in preferred stock, liquidation value | $			$ 8,000,000,000
Investment in preferred stock, stated dividend rate							9.00%
Kraft Heinz (previously Heinz Holding) [Member] | Berkshire Hathaway (Parent) [Member] | Common Stock, Cumulative Compounding Preferred Stock and Warrants [Member]
Schedule of Equity Method Investments [Line Items]
Purchase of preferred stock, common stock and warrants | $			$ 12,250,000,000
Kraft Heinz (previously Heinz Holding) [Member] | 3G Capital (venture partner) [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage			50.00%
Kraft Heinz (previously Heinz Holding) [Member] | 3G Capital (venture partner) [Member] | Common Stock [Member]
Schedule of Equity Method Investments [Line Items]
Number of shares acquired			425,000,000
Purchase of common stock | $			$ 4,250,000,000
Management and Directors [Member] | Kraft Heinz (previously Heinz Holding) [Member] | Common Stock [Member]
Schedule of Equity Method Investments [Line Items]
Common shares reserved for issuance under equity grants, including stock options			39,600,000
Kraft [Member]
Schedule of Equity Method Investments [Line Items]
Minimum annual revenues of Kraft | $							$ 18,000,000,000
Kraft [Member] | Kraft Heinz (previously Heinz Holding) [Member]
Schedule of Equity Method Investments [Line Items]
Ratio of common stock shares to be issued per Kraft common stock share					1
Dividend to be received by Kraft shareholders per share | $ / shares					$ 16.50
Subsequent Event [Member] | Kraft Heinz (previously Heinz Holding) [Member] | Common Stock [Member]
Schedule of Equity Method Investments [Line Items]
Reverse stock split ratio		0.443332
Subsequent Event [Member] | Kraft Heinz (previously Heinz Holding) [Member] | Berkshire Hathaway (Parent) [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage		52.50%
Equity method investment ownership percentage after transactions	26.90%
Subsequent Event [Member] | Kraft Heinz (previously Heinz Holding) [Member] | Berkshire Hathaway (Parent) [Member] | Common Stock [Member]
Schedule of Equity Method Investments [Line Items]
Number of shares acquired		262,900,000
Purchase of common stock | $		$ 5,260,000,000
Investment, number of shares owned		325,400,000
Subsequent Event [Member] | Kraft Heinz (previously Heinz Holding) [Member] | Berkshire Hathaway Inc. and 3G Capital [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage after transactions	51.00%
Subsequent Event [Member] | Kraft Heinz (previously Heinz Holding) [Member] | 3G Capital (venture partner) [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment ownership percentage after transactions	24.20%
Subsequent Event [Member] | Kraft Heinz (previously Heinz Holding) [Member] | 3G Capital (venture partner) [Member] | Common Stock [Member]
Schedule of Equity Method Investments [Line Items]
Number of shares acquired		237,100,000
Purchase of common stock | $		$ 4,740,000,000
Subsequent Event [Member] | Kraft [Member] | Kraft Heinz (previously Heinz Holding) [Member] | Common Stock [Member]
Schedule of Equity Method Investments [Line Items]
Number of new shares issued	592,000,000
Scenario, Forecast [Member] | Kraft Heinz (previously Heinz Holding) [Member] | Berkshire Hathaway (Parent) [Member] | Common Stock [Member]
Schedule of Equity Method Investments [Line Items]
Non-cash pre-tax holding gain | $						$ 7,000,000,000