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

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

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Weighted average interest rate of debt outstanding.

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

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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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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No definition available.

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Note to Condensed Financial Information - Narrative (Detail) $ in Millions, € in Billions, ¥ in Billions		1 Months Ended				2 Months Ended		12 Months Ended
	Oct. 19, 2022 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2022 JPY (¥)	Jan. 31, 2022 USD ($)	Jan. 31, 2022 JPY (¥)	Apr. 30, 2023 USD ($)	Feb. 28, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2022 JPY (¥)	Dec. 31, 2022 EUR (€)
Condensed Financial Statements, Captions [Line Items]
Debt maturities: 2023		$ 12,962						$ 12,962
Debt maturities: 2024		6,256						6,256
Debt maturities: 2025		7,041						7,041
Debt maturities: 2026		4,952						4,952
Debt maturities: 2027		4,556						4,556
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: 2023		7,080						7,080
Debt maturities: 2024		1,975						1,975
Debt maturities: 2025		3,122						3,122
Debt maturities: 2026		3,454						3,454
Debt maturities: 2027		2,870						2,870
Berkshire Hathaway Inc. (Parent) [Member]
Condensed Financial Statements, Captions [Line Items]
Repayments of borrowings								602	$ 2,167	$ 1,151
Principal amount of debt issued											¥ 1,029.0	€ 6.9
Debt maturities: 2023		4,300						4,300
Debt maturities: 2024		1,900						1,900
Debt maturities: 2025		2,000						2,000
Debt maturities: 2026		3,200						3,200
Debt maturities: 2027		2,100						2,100
Guarantees of subsidiary debt		21,700						$ 21,700
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Subsequent Event [Member]
Condensed Financial Statements, Captions [Line Items]
Repayments of borrowings							$ 1,100
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Forecast [Member]
Condensed Financial Statements, Captions [Line Items]
Repayments of borrowings						$ 3,200
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member]
Condensed Financial Statements, Captions [Line Items]
Principal amount of debt issued				$ 1,100	¥ 128.5
Weighted average interest rate, percentage				0.50%	0.50%
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Minimum [Member]
Condensed Financial Statements, Captions [Line Items]
Debt maturity year				2027	2027
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Maximum [Member]
Condensed Financial Statements, Captions [Line Items]
Debt maturity year				2052	2052
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2025 To 2052 [Member]
Condensed Financial Statements, Captions [Line Items]
Principal amount of debt issued		$ 840	¥ 115.0
Weighted average interest rate, percentage		1.10%						1.10%			1.10%	1.10%
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2025 To 2052 [Member] \| Minimum [Member]
Condensed Financial Statements, Captions [Line Items]
Debt maturity year		2025	2025
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2025 To 2052 [Member] \| Maximum [Member]
Condensed Financial Statements, Captions [Line Items]
Debt maturity year		2052	2052
Berkshire Hathaway Inc. (Parent) [Member] \| The Kraft Heinz Company [Member]
Condensed Financial Statements, Captions [Line Items]
Equity method investment ownership percentage after transactions								26.60%