Year the debt matures, in CCYY format.

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Aggregate amount of short-term and long-term debt maturing or scheduled to be repaid within the next twelve months following the date of the latest balance sheet presented in the financial statements.

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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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Weighted average interest rate of debt outstanding.

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Amount of long-term debt and lease obligation, classified as noncurrent.

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

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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, 2019 USD ($)	Dec. 31, 2019 JPY (¥)	Dec. 31, 2019 GBP (£)	Dec. 31, 2019 EUR (€)	Dec. 31, 2018 USD ($)
Debt Instrument [Line Items]
Notes payable and other borrowings		¥ 430	£ 1,750	€ 6,850
Principal payments on debt - 2020	$ 10,420
Principal payments on debt - 2021	5,471
Principal payments on debt - 2022	4,958
Principal payments on debt - 2023	9,402
Principal payments on debt - 2024	5,080
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	37,590				$ 34,975
Principal payments on debt - 2020	4,097
Principal payments on debt - 2021	3,246
Principal payments on debt - 2022	1,609
Principal payments on debt - 2023	5,341
Principal payments on debt - 2024	2,190
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	65,778				62,515
Principal payments on debt - 2020	6,323
Principal payments on debt - 2021	2,225
Principal payments on debt - 2022	3,349
Principal payments on debt - 2023	4,061
Principal payments on debt - 2024	2,890
Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	19,903				16,871
Principal payments on debt - 2020	1,122
Principal payments on debt - 2021	2,117
Principal payments on debt - 2022	613
Principal payments on debt - 2023	3,958
Principal payments on debt - 2024	2,120
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 8,324				9,065
Weighted average interest rate, percentage	3.20%	3.20%	3.20%	3.20%
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| U.S. Dollar Denominated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| U.S. Dollar Denominated [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2047
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Euro Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 7,641				7,806
Weighted average interest rate, percentage	1.10%	1.10%	1.10%	1.10%
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Euro Denominated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Euro Denominated [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2035
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Japanese Yen Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 3,938
Weighted average interest rate, percentage	0.50%	0.50%	0.50%	0.50%
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Japanese Yen Denominated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2024
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Japanese Yen Denominated [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2049
Subsidiaries [Member] \| Insurance and Other [Member]
Debt Instrument [Line Items]
Other borrowings	$ 5,262				5,597
Short-term debt	$ 1,472				1,857
Weighted average interest rate, percentage	4.00%	4.00%	4.00%	4.00%
Short-term debt, weighted average interest rate	3.90%	3.90%	3.90%	3.90%
Subsidiaries [Member] \| Insurance and Other [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Subsidiaries [Member] \| Insurance and Other [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2045
Subsidiaries [Member] \| Insurance and Other [Member] \| U.S. Dollar Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 8,679				10,650
Weighted average interest rate, percentage	4.10%	4.10%	4.10%	4.10%
Subsidiaries [Member] \| Insurance and Other [Member] \| U.S. Dollar Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Subsidiaries [Member] \| Insurance and Other [Member] \| U.S. Dollar Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2049
Subsidiaries [Member] \| Insurance and Other [Member] \| Great Britain Pound Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 2,274
Weighted average interest rate, percentage	2.50%	2.50%	2.50%	2.50%
Subsidiaries [Member] \| Insurance and Other [Member] \| Great Britain Pound Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2039
Subsidiaries [Member] \| Insurance and Other [Member] \| Great Britain Pound Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2059
Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage	4.60%	4.60%	4.60%	4.60%
Senior unsecured debt	$ 8,581				8,577
Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2049
Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy Subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 30,772				28,196
Weighted average interest rate, percentage	4.50%	4.50%	4.50%	4.50%
Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy Subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2064
Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Short-term debt	$ 3,214				2,516
Short-term debt, weighted average interest rate	2.50%	2.50%	2.50%	2.50%
Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| Burlington Northern Santa Fe and subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 23,211				$ 23,226
Weighted average interest rate, percentage	4.60%	4.60%	4.60%	4.60%
Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| Burlington Northern Santa Fe and subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| Burlington Northern Santa Fe and subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2097