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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Amount of short-term and long-term debt and lease obligation.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Weighted average interest rate of debt outstanding.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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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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Notes payable and other borrowings - Narrative (Detail) € in Millions, £ in Millions, $ in Millions, ¥ in Billions	1 Months Ended				3 Months Ended
	Apr. 30, 2022 USD ($)	Apr. 30, 2022 GBP (£)	Jan. 31, 2022 USD ($)	Jan. 31, 2022 JPY (¥)	Mar. 31, 2022 USD ($)	Mar. 31, 2022 EUR (€)	Mar. 31, 2021 USD ($)	Mar. 31, 2022 JPY (¥)	Mar. 31, 2022 EUR (€)	Mar. 31, 2022 GBP (£)	Dec. 31, 2021 USD ($)
Debt Instrument [Line Items]
Notes payable and other borrowings								¥ 914.0	€ 8,150	£ 1,750
Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued			$ 1,100	¥ 128.5
Weighted average interest rate, percentage			0.50%	0.50%
Minimum [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Debt maturity year			2027	2027
Maximum [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Debt maturity year			2052	2052
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings					$ 44,890						$ 39,272
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Guarantee obligation					$ 3,800
Insurance and Other [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage					4.10%			4.10%	4.10%	4.10%
Insurance and Other [Member] \| Senior Notes [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Repayments of borrowings			$ 600
Gains (loss) attributable to changes in foreign currency exchange rates					$ 716		$ 720
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Principal amount of debt issued					$ 4,500
Weighted average interest rate, percentage					3.40%			3.40%	3.40%	3.40%
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2030 To 2034 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Principal amount of debt issued					$ 1,400	€ 1,250
Weighted average interest rate, percentage					1.80%			1.80%	1.80%	1.80%
Insurance and Other [Member] \| Minimum [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year					2022	2022
Insurance and Other [Member] \| Minimum [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Debt maturity year					2027	2027
Insurance and Other [Member] \| Minimum [Member] \| Senior Notes [Member] \| Debt Due 2030 To 2034 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Debt maturity year					2030	2030
Insurance and Other [Member] \| Maximum [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year					2045	2045
Insurance and Other [Member] \| Maximum [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Debt maturity year					2052	2052
Insurance and Other [Member] \| Maximum [Member] \| Senior Notes [Member] \| Debt Due 2030 To 2034 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Debt maturity year					2034	2034
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings					$ 74,771						$ 74,990
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage					4.30%			4.30%	4.30%	4.30%
Railroad, Utilities and Energy [Member] \| 4.6% Senior Notes Due [Member] \| Berkshire Hathaway Energy [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 1,000
Debt maturity year	2053	2053
Debt instrument, interest rate, stated percentage	4.60%	4.60%
Railroad, Utilities and Energy [Member] \| 3.25% Senior Notes Due [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| £		£ 350
Debt maturity year	2052	2052
Debt instrument, interest rate, stated percentage	3.25%	3.25%
Railroad, Utilities and Energy [Member] \| Minimum [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Debt maturity year					2023	2023
Railroad, Utilities and Energy [Member] \| Maximum [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Debt maturity year					2051	2051