Year the debt matures, in CCYY format.

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- Definition

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

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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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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

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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Weighted average interest rate of short-term debt outstanding calculated at point in time.

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- Definition

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	9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2023 EUR (€)	Sep. 30, 2023 GBP (£)	Sep. 30, 2023 JPY (¥)	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Notes payable and other borrowings		€ 6,850	£ 1,750	¥ 1,137
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 40,941				$ 46,538
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 3,737				6,231
Weighted average interest rate, percentage	3.50%	3.50%	3.50%	3.50%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| U.S. Dollar Denominated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2025
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	$ 5,884				7,344
Weighted average interest rate, percentage	1.10%	1.10%	1.10%	1.10%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Euro Denominated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2024
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	$ 7,585				7,818
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	2024
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	$ 4,951				5,967
Short-term debt	$ 907				1,310
Weighted average interest rate, percentage	4.60%	4.60%	4.60%	4.60%
Short-term borrowings, weighted average interest rate	7.10%	7.10%	7.10%	7.10%
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	$ 14,462				14,458
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	$ 1,316				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] \| Great Britain Pound Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 2,099				2,078
Weighted average interest rate, percentage	2.50%	2.50%	2.50%	2.50%
Insurance and Other [Member] \| Subsidiaries [Member] \| Great Britain Pound Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2039
Insurance and Other [Member] \| Subsidiaries [Member] \| Great Britain Pound Denominated [Member] \| 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	$ 83,840				76,206
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Pilot Travel Centers ("PTC") [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 5,999
Weighted average interest rate, percentage	7.20%	7.20%	7.20%	7.20%
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Minimum [Member] \| Pilot Travel Centers ("PTC") [Member]
Debt Instrument [Line Items]
Debt maturity year	2023
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Maximum [Member] \| Pilot Travel Centers ("PTC") [Member]
Debt Instrument [Line Items]
Debt maturity year	2028
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage	4.40%	4.40%	4.40%	4.40%
Senior unsecured debt	$ 13,600				13,996
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	$ 39,119				37,639
Weighted average interest rate, percentage	4.40%	4.40%	4.40%	4.40%
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	$ 1,617				1,119
Short-term borrowings, weighted average interest rate	5.90%	5.90%	5.90%	5.90%
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Burlington Northern Santa Fe ("BNSF") and subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 23,505				$ 23,452
Weighted average interest rate, percentage	4.60%	4.60%	4.60%	4.60%
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