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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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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Notes payable and other borrowings (Detail) € in Millions, £ in Millions, $ in Millions, ¥ in Billions	12 Months Ended
	Dec. 31, 2022 USD ($)	Dec. 31, 2022 EUR (€)	Dec. 31, 2022 GBP (£)	Dec. 31, 2022 JPY (¥)	Dec. 31, 2021 USD ($)
Debt Instrument [Line Items]
Notes payable and other borrowings		€ 8,150	£ 1,750	¥ 1,029
Principal payments on debt - 2023	$ 12,962
Principal payments on debt - 2024	6,256
Principal payments on debt - 2025	7,041
Principal payments on debt - 2026	4,952
Principal payments on debt - 2027	4,556
Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	21,393				$ 21,409
Principal payments on debt - 2023	4,300
Principal payments on debt - 2024	1,900
Principal payments on debt - 2025	2,000
Principal payments on debt - 2026	3,200
Principal payments on debt - 2027	2,100
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	46,538				39,272
Principal payments on debt - 2023	7,080
Principal payments on debt - 2024	1,975
Principal payments on debt - 2025	3,122
Principal payments on debt - 2026	3,454
Principal payments on debt - 2027	2,870
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 6,231				6,820
Weighted average interest rate, percentage	3.20%	3.20%	3.20%	3.20%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| U.S. Dollar Denominated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2023
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| U.S. Dollar Denominated [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2047
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Euro Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 7,344				7,792
Weighted average interest rate, percentage	1.00%	1.00%	1.00%	1.00%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Euro Denominated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2023
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Euro Denominated [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2041
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Japanese Yen Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 7,818				6,797
Weighted average interest rate, percentage	0.70%	0.70%	0.70%	0.70%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Japanese Yen Denominated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2023
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Japanese Yen Denominated [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2060
Insurance and Other [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 5,967				4,438
Short-term debt	$ 1,310				342
Weighted average interest rate, percentage	4.30%	4.30%	4.30%	4.30%
Short-term borrowings, weighted average interest rate	5.80%	5.80%	5.80%	5.80%
Insurance and Other [Member] \| Subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2023
Insurance and Other [Member] \| Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2051
Insurance and Other [Member] \| Subsidiaries [Member] \| U.S. Dollar Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 14,458				10,758
Weighted average interest rate, percentage	3.60%	3.60%	3.60%	3.60%
Insurance and Other [Member] \| Subsidiaries [Member] \| U.S. Dollar Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2027
Insurance and Other [Member] \| Subsidiaries [Member] \| U.S. Dollar Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2052
Insurance and Other [Member] \| Subsidiaries [Member] \| Euro Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 1,332
Weighted average interest rate, percentage	1.80%	1.80%	1.80%	1.80%
Insurance and Other [Member] \| Subsidiaries [Member] \| Euro Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2030
Insurance and Other [Member] \| Subsidiaries [Member] \| Euro Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2034
Insurance and Other [Member] \| Subsidiaries [Member] \| United Kingdom, Pounds \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 2,078				2,325
Weighted average interest rate, percentage	2.50%	2.50%	2.50%	2.50%
Insurance and Other [Member] \| Subsidiaries [Member] \| United Kingdom, Pounds \| Berkshire Hathaway Finance Corporation [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2039
Insurance and Other [Member] \| Subsidiaries [Member] \| United Kingdom, Pounds \| Berkshire Hathaway Finance Corporation [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2059
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 76,206				74,990
Principal payments on debt - 2023	5,882
Principal payments on debt - 2024	4,281
Principal payments on debt - 2025	3,919
Principal payments on debt - 2026	1,498
Principal payments on debt - 2027	$ 1,686
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%
Senior unsecured debt	$ 13,996				13,003
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2023
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2053
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy Subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 37,639				36,759
Weighted average interest rate, percentage	4.30%	4.30%	4.30%	4.30%
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy Subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2023
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2064
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Short-term debt	$ 1,119				2,009
Short-term borrowings, weighted average interest rate	5.20%	5.20%	5.20%	5.20%
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Burlington Northern Santa Fe ("BNSF") and subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 23,452				$ 23,219
Weighted average interest rate, percentage	4.50%	4.50%	4.50%	4.50%
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Burlington Northern Santa Fe ("BNSF") and subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2023
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Burlington Northern Santa Fe ("BNSF") and subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2097