Notes payable and other borrowings - Narrative (Detail) - USD ($)
$ in Millions |
1 Months Ended |
12 Months Ended |
Jan. 31, 2019 |
Aug. 31, 2018 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
| Berkshire Hathaway Inc. (Parent) [Member] |
|
|
|
|
|
| Debt Instrument [Line Items] |
|
|
|
|
|
| Gain (loss) attributable to changes in foreign currency exchange rates |
|
|
$ 366
|
$ (1,008)
|
$ 244
|
| Repayments of borrowings |
|
|
$ 1,563
|
1,145
|
1,125
|
| Subsidiaries [Member] | Insurance and Other [Member] |
|
|
|
|
|
| Debt Instrument [Line Items] |
|
|
|
|
|
| Weighted average interest rate, percentage |
|
|
4.00%
|
|
|
| Euro Denominated [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Insurance and Other [Member] |
|
|
|
|
|
| Debt Instrument [Line Items] |
|
|
|
|
|
| Weighted average interest rate, percentage |
|
|
1.10%
|
|
|
| Euro Denominated [Member] | Senior Notes [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Insurance and Other [Member] |
|
|
|
|
|
| Debt Instrument [Line Items] |
|
|
|
|
|
| Gain (loss) attributable to changes in foreign currency exchange rates |
|
|
$ 366
|
$ (990)
|
$ 264
|
| Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member] | Berkshire Hathaway Inc. (Parent) [Member] | Insurance and Other [Member] |
|
|
|
|
|
| Debt Instrument [Line Items] |
|
|
|
|
|
| Guarantee obligation |
|
|
1,700
|
|
|
| Berkshire Hathaway Energy and Subsidiaries [Member] | Debt Due 2020 To 2049 [Member] | Subsidiaries [Member] | Railroad, Utilities and Energy [Member] |
|
|
|
|
|
| Debt Instrument [Line Items] |
|
|
|
|
|
| Principal amount of debt issued |
|
|
$ 5,500
|
|
|
| Weighted average interest rate, percentage |
|
|
3.60%
|
|
|
| BNSF [Member] | Debentures Due 2048 [Member] | Senior Unsecured Debentures [Member] | Subsidiaries [Member] | Railroad, Utilities and Energy [Member] |
|
|
|
|
|
| Debt Instrument [Line Items] |
|
|
|
|
|
| Principal amount of debt issued |
|
|
$ 1,500
|
|
|
| Weighted average interest rate, percentage |
|
|
4.10%
|
|
|
| Berkshire Hathaway Finance Corporation [Member] | Subsidiaries [Member] | Insurance and Other [Member] |
|
|
|
|
|
| Debt Instrument [Line Items] |
|
|
|
|
|
| Weighted average interest rate, percentage |
|
|
3.40%
|
|
|
| Berkshire Hathaway Finance Corporation [Member] | Senior Notes [Member] | Subsidiaries [Member] | Insurance and Other [Member] |
|
|
|
|
|
| Debt Instrument [Line Items] |
|
|
|
|
|
| Repayments of borrowings |
|
|
$ 4,600
|
|
|
| Berkshire Hathaway Finance Corporation [Member] | Notes Due 2048 at 4.2% [Member] | Senior Notes [Member] | Subsidiaries [Member] | Insurance and Other [Member] |
|
|
|
|
|
| Debt Instrument [Line Items] |
|
|
|
|
|
| Principal amount of debt issued |
|
$ 2,350
|
|
|
|
| Debt instrument, interest rate, stated percentage |
|
4.20%
|
|
|
|
| Berkshire Hathaway Finance Corporation [Member] | Subsequent Event [Member] | Subsidiaries [Member] | Insurance and Other [Member] |
|
|
|
|
|
| Debt Instrument [Line Items] |
|
|
|
|
|
| Repayments of borrowings |
$ 950
|
|
|
|
|
| Berkshire Hathaway Finance Corporation [Member] | Subsequent Event [Member] | Notes Due 2048 at 4.25% [Member] | Senior Notes [Member] | Subsidiaries [Member] | Insurance and Other [Member] |
|
|
|
|
|
| Debt Instrument [Line Items] |
|
|
|
|
|
| Principal amount of debt issued |
$ 1,250
|
|
|
|
|
| Debt instrument, interest rate, stated percentage |
4.25%
|
|
|
|
|