Year the debt matures, in CCYY format.

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Face (par) amount of debt instrument at time of issuance.

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The average effective interest rate during the reporting period.

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Amount of other-than-temporary decline in value that has been recognized against investment accounted for under equity method of accounting.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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Note to Condensed Financial Information - Narrative (Detail) $ in Millions, € in Billions, ¥ in Billions	3 Months Ended	12 Months Ended
	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2025 JPY (¥)	Dec. 31, 2025 JPY (¥)	Dec. 31, 2025 EUR (€)
Condensed Financial Statements, Captions [Line Items]
Equity method investment, other-than-temporary impairment charge		$ 10,681
Debt maturities: 2026		9,782
Debt maturities: 2027		6,631
Debt maturities: 2028		5,193
Debt maturities: 2029		6,336
Debt maturities: 2030		5,793
Insurance and Other [Member]
Condensed Financial Statements, Captions [Line Items]
Debt maturities: 2026		5,759
Debt maturities: 2027		4,972
Debt maturities: 2028		3,424
Debt maturities: 2029		2,603
Debt maturities: 2030		3,222
The Kraft Heinz Company [Member]
Condensed Financial Statements, Captions [Line Items]
Equity method investment, other-than-temporary impairment charge	$ 5,000
Berkshire Hathaway Inc. (Parent) [Member]
Condensed Financial Statements, Captions [Line Items]
Principal amount of debt issued				¥ 2,343.0	€ 3.6
Debt maturities: 2026		4,200
Debt maturities: 2027		4,100
Debt maturities: 2028		3,400
Debt maturities: 2029		2,600
Debt maturities: 2030		850
Guarantees of subsidiary debt		20,100
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Senior Notes and Term Loan Due 2028 to 2055 [Member]
Condensed Financial Statements, Captions [Line Items]
Principal amount of debt issued		$ 3,000	¥ 451.6
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Senior Notes and Term Loan Due 2028 to 2055 [Member] \| Minimum [Member]
Condensed Financial Statements, Captions [Line Items]
Interest rate during period		1.35%	1.35%
Debt maturity year		2028	2028
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Senior Notes and Term Loan Due 2028 to 2055 [Member] \| Maximum [Member]
Condensed Financial Statements, Captions [Line Items]
Interest rate during period		3.12%	3.12%
Debt maturity year		2055	2055
Berkshire Hathaway Inc. (Parent) [Member] \| The Kraft Heinz Company [Member]
Condensed Financial Statements, Captions [Line Items]
Equity method investment ownership percentage after transactions		27.50%	27.50%
Equity method investment, other-than-temporary impairment charge		$ 5,000