Notes payable and other borrowings (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Principal payments on debt - 2017	$ 10,256
Principal payments on debt - 2018	12,011
Principal payments on debt - 2019	7,396
Principal payments on debt - 2020	4,389
Principal payments on debt - 2021	4,342
Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	17,703	$ 9,799
Principal payments on debt - 2017	1,101
Principal payments on debt - 2018	1,551
Principal payments on debt - 2019	754
Principal payments on debt - 2020	1,054
Principal payments on debt - 2021	1,500
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	27,175	14,599
Principal payments on debt - 2017	3,329
Principal payments on debt - 2018	3,022
Principal payments on debt - 2019	1,362
Principal payments on debt - 2020	1,650
Principal payments on debt - 2021	1,824
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 17,703	9,799
Weighted average interest rate, percentage	2.20%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2017
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2047
Insurance and Other [Member] \| Insurance and Other Subsidiaries [Member]
Debt Instrument [Line Items]
Short-term borrowings	$ 2,094	1,989
Other borrowings	$ 7,378	2,811
Short-term debt, weighted average interest rate	2.50%
Weighted average interest rate, percentage	4.00%
Insurance and Other [Member] \| Insurance and Other Subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2017
Insurance and Other [Member] \| Insurance and Other Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2045
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 59,085	57,739
Principal payments on debt - 2017	3,610
Principal payments on debt - 2018	4,283
Principal payments on debt - 2019	2,935
Principal payments on debt - 2020	2,123
Principal payments on debt - 2021	$ 1,741
Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage	5.10%
Senior unsecured debt	$ 7,818	7,814
Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2017
Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2045
Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy Subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 29,223	28,188
Weighted average interest rate, percentage	4.70%
Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy Subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2017
Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2064
Railroad, Utilities and Energy [Member] \| BNSF [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 22,044	21,737
Weighted average interest rate, percentage	4.80%
Railroad, Utilities and Energy [Member] \| BNSF [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2017
Railroad, Utilities and Energy [Member] \| BNSF [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2097
Finance and Financial Products [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 15,384	11,951
Principal payments on debt - 2017	3,317
Principal payments on debt - 2018	4,706
Principal payments on debt - 2019	3,099
Principal payments on debt - 2020	616
Principal payments on debt - 2021	777
Finance and Financial Products [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 14,423	10,679
Weighted average interest rate, percentage	2.50%
Finance and Financial Products [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2017
Finance and Financial Products [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2043
Finance and Financial Products [Member] \| Other Finance Subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 961	$ 1,272
Weighted average interest rate, percentage	4.90%
Finance and Financial Products [Member] \| Other Finance Subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2017
Finance and Financial Products [Member] \| Other Finance Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2036

Year the debt matures, in CCYY format.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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Weighted average interest rate of debt outstanding.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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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