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v3.25.2

Notes payable and other borrowings - Narrative (Detail) € in Millions, £ in Millions, $ in Millions, ¥ in Billions | 1 Months Ended | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jul. 31, 2025 USD ($) | Jul. 31, 2025 JPY (¥) | Apr. 30, 2025 USD ($) | Apr. 30, 2025 JPY (¥) | Jun. 30, 2025 USD ($) | Jun. 30, 2024 USD ($) | Jun. 30, 2025 USD ($) | Jun. 30, 2024 USD ($) | Jun. 30, 2025 JPY (¥) | Jun. 30, 2025 EUR (€) | Jun. 30, 2025 GBP (£) | Dec. 31, 2024 USD ($)
Berkshire Hathaway Inc. (Parent) [Member] | Berkshire Hathaway Finance Corporation [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Notes payable and other borrowings |  |  |  |  |  |  |  |  | ¥ 2,036.0 | € 4,850 | £ 1,750 |
Line of Credit and Commercial Paper Facilities [Member] | Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Unused and available lines of credit |  |  |  |  | $ 11,000 |  | $ 11,000 |  |  |  |  |
Line of Credit and Commercial Paper Facilities [Member] | Subsidiaries [Member] | Berkshire Hathaway Energy and Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Unused and available lines of credit |  |  |  |  | 9,800 |  | 9,800 |  |  |  |  |
Insurance and Other [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Notes payable and other borrowings |  |  |  |  | 45,040 |  | 45,040 |  |  |  |  | $ 44,885
Insurance and Other [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Guarantee obligation |  |  |  |  | 1,700 |  | 1,700 |  |  |  |  |
Insurance and Other [Member] | Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Short-term borrowings |  |  |  |  | $ 1,299 |  | $ 1,299 |  |  |  |  | 1,315
Weighted average interest rate, percentage |  |  |  |  | 5.00% |  | 5.00% |  | 5.00% | 5.00% | 5.00% |
Notes payable and other borrowings |  |  |  |  | $ 3,572 |  | $ 3,572 |  |  |  |  | 4,564
Insurance and Other [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Repayments of borrowings |  |  |  |  |  |  | 1,600 |  |  |  |  |
Insurance and Other [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Berkshire Hathaway Finance Corporation [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Gains (loss) attributable to changes in foreign currency exchange rates |  |  |  |  | (1,200) | $ 588 | $ (2,100) | $ 1,400 |  |  |  |
Insurance and Other [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Debt Due 2028 to 2055 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt issued |  |  | $ 632 | ¥ 90.0 |  |  |  |  |  |  |  |
Interest rate during period |  |  | 1.637% | 1.637% |  |  |  |  |  |  |  |
Insurance and Other [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Debt Due 2030 to 2040 [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of debt issued | $ 1,000 | ¥ 151.5 |  |  |  |  |  |  |  |  |  |
Interest rate during period | 2.306% | 2.306% |  |  |  |  |  |  |  |  |  |
Insurance and Other [Member] | Minimum [Member] | Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  |  |  |  |  | 2025 |  |  |  |  |
Insurance and Other [Member] | Minimum [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Debt Due 2028 to 2055 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  | 2028 | 2028 |  |  |  |  |  |  |  |
Insurance and Other [Member] | Minimum [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Debt Due 2030 to 2040 [Member] | Subsequent Event [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 |  |  |  |  |  |  | 2051 |  |  |  |  |
Insurance and Other [Member] | Maximum [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Debt Due 2028 to 2055 [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  | 2055 | 2055 |  |  |  |  |  |  |  |
Insurance and Other [Member] | Maximum [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Debt Due 2030 to 2040 [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year | 2040 | 2040 |  |  |  |  |  |  |  |  |  |
Railroad, Utilities and Energy [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Notes payable and other borrowings |  |  |  |  | 81,980 |  | $ 81,980 |  |  |  |  | 79,877
Railroad, Utilities and Energy [Member] | Subsidiaries [Member] | Berkshire Hathaway Energy and Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Short-term borrowings |  |  |  |  | $ 1,687 |  | $ 1,687 |  |  |  |  | 1,123
Railroad, Utilities and Energy [Member] | Subsidiaries [Member] | Berkshire Hathaway Energy Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate, percentage |  |  |  |  | 4.70% |  | 4.70% |  | 4.70% | 4.70% | 4.70% |
Notes payable and other borrowings |  |  |  |  | $ 44,982 |  | $ 44,982 |  |  |  |  | $ 42,150
Railroad, Utilities and Energy [Member] | Subsidiaries [Member] | Term Debt [Member] | Berkshire Hathaway Energy Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Repayments of borrowings |  |  |  |  |  |  | 2,000 |  |  |  |  |
Short-term borrowings |  |  |  |  | $ 564 |  | 564 |  |  |  |  |
Principal amount of debt issued |  |  |  |  |  |  | $ 2,700 |  |  |  |  |
Weighted average interest rate, percentage |  |  |  |  | 6.50% |  | 6.50% |  | 6.50% | 6.50% | 6.50% |
Railroad, Utilities and Energy [Member] | Senior Unsecured Debentures [Member] | Subsidiaries [Member] | BNSF [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Repayments of borrowings |  |  |  |  |  |  | $ 530 |  |  |  |  |
Principal amount of debt issued |  |  |  |  |  |  | $ 900 |  |  |  |  |
Debt instrument, interest rate, stated percentage |  |  |  |  | 5.80% |  | 5.80% |  | 5.80% | 5.80% | 5.80% |
Debt maturity year |  |  |  |  |  |  | 2056 |  |  |  |  |
Railroad, Utilities and Energy [Member] | Minimum [Member] | Subsidiaries [Member] | Berkshire Hathaway Energy Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  |  |  |  |  | 2025 |  |  |  |  |
Railroad, Utilities and Energy [Member] | Minimum [Member] | Subsidiaries [Member] | Term Debt [Member] | Berkshire Hathaway Energy Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  |  |  |  |  | 2035 |  |  |  |  |
Railroad, Utilities and Energy [Member] | Maximum [Member] | Subsidiaries [Member] | Berkshire Hathaway Energy Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  |  |  |  |  | 2064 |  |  |  |  |
Railroad, Utilities and Energy [Member] | Maximum [Member] | Subsidiaries [Member] | Term Debt [Member] | Berkshire Hathaway Energy Subsidiaries [Member] |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Debt maturity year |  |  |  |  |  |  | 2055 |  |  |  |  |

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