Year the debt matures, in CCYY format.

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The principal amount of new debt issued during the period, excluding premium or discount, if any.

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The unpaid balance of subsidiary debt that the parent entity has guaranteed full payment of present and future obligations when due.

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Aggregate amount of short-term and long-term debt maturing or scheduled to be repaid within the next twelve months following the date of the latest balance sheet presented in the financial statements.

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No definition available.

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Date when the acquirer obtains control of the acquiree, in YYYY-MM-DD format.

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- Definition

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

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- Definition

Weighted average interest rate of debt outstanding.

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No definition available.

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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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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Amount of cash outflow for short-term and long-term debt. Excludes payment of lease obligation.

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- Definition

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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Note to Condensed Financial Information - Narrative (Detail) $ in Millions, € in Billions, ¥ in Billions		12 Months Ended
	Oct. 19, 2022 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2023 JPY (¥)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2023 JPY (¥)	Dec. 31, 2023 EUR (€)
Condensed Financial Statements, Captions [Line Items]
Debt maturities: 2024		$ 13,859
Debt maturities: 2025		7,048
Debt maturities: 2026		6,053
Debt maturities: 2027		4,549
Debt maturities: 2028		6,433
Alleghany Corporation [Member]
Condensed Financial Statements, Captions [Line Items]
Business acquisition, cash consideration	$ 11,500
Business acquisition, effective date of acquisition	Oct. 19, 2022
Insurance and Other [Member]
Condensed Financial Statements, Captions [Line Items]
Debt maturities: 2024		3,295
Debt maturities: 2025		3,076
Debt maturities: 2026		4,499
Debt maturities: 2027		2,877
Debt maturities: 2028		1,413
Berkshire Hathaway Inc. (Parent) [Member]
Condensed Financial Statements, Captions [Line Items]
Repayments of borrowings		4,310		$ 602	$ 2,167
Principal amount of debt issued						¥ 1,259.0	€ 5.6
Debt maturities: 2024		1,900
Debt maturities: 2025		2,000
Debt maturities: 2026		4,400
Debt maturities: 2027		2,000
Debt maturities: 2028		1,400
Guarantees of subsidiary debt		20,900
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member]
Condensed Financial Statements, Captions [Line Items]
Repayments of borrowings		4,300
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2026 To 2058 [Member]
Condensed Financial Statements, Captions [Line Items]
Principal amount of debt issued		$ 2,050	¥ 286.4
Weighted average interest rate, percentage		1.15%				1.15%	1.15%
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2026 To 2058 [Member] \| Minimum [Member]
Condensed Financial Statements, Captions [Line Items]
Debt maturity year		2026	2026
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2026 To 2058 [Member] \| Maximum [Member]
Condensed Financial Statements, Captions [Line Items]
Debt maturity year		2058	2058
Berkshire Hathaway Inc. (Parent) [Member] \| The Kraft Heinz Company [Member]
Condensed Financial Statements, Captions [Line Items]
Equity method investment ownership percentage after transactions		26.70%	26.70%