Year the debt matures, in CCYY format.

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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- Definition

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.

+ References

No definition available.

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

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

+ References

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Notes payable and other borrowings (Detail) € in Millions, £ in Millions, $ in Millions, ¥ in Billions	9 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2020 EUR (€)	Sep. 30, 2020 JPY (¥)	Sep. 30, 2020 GBP (£)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Notes payable and other borrowings		€ 6,850	¥ 625.5	£ 1,750
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 68,800				$ 65,778
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	38,891				37,590
Insurance and Other [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Other borrowings	4,676				5,262
Short-term borrowings	$ 960				1,472
Weighted average interest rate, percentage	4.20%	4.20%	4.20%	4.20%
Short-term borrowings, weighted average interest rate	2.70%	2.70%	2.70%	2.70%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 8,320				8,324
Weighted average interest rate, percentage	3.20%	3.20%	3.20%	3.20%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Euro Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 7,986				7,641
Weighted average interest rate, percentage	1.00%	1.00%	1.00%	1.00%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Japanese Yen Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 5,902				3,938
Weighted average interest rate, percentage	0.60%	0.60%	0.60%	0.60%
Insurance and Other [Member] \| Minimum [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Insurance and Other [Member] \| Minimum [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Insurance and Other [Member] \| Minimum [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Euro Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2021
Insurance and Other [Member] \| Minimum [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Japanese Yen Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2023
Insurance and Other [Member] \| Maximum [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2045
Insurance and Other [Member] \| Maximum [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2047
Insurance and Other [Member] \| Maximum [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Euro Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2035
Insurance and Other [Member] \| Maximum [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Japanese Yen Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2060
Berkshire Hathaway Energy [Member] \| Railroad, Utilities and Energy [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage	4.50%	4.50%	4.50%	4.50%
Senior unsecured debt	$ 11,462				8,581
Berkshire Hathaway Energy [Member] \| Railroad, Utilities and Energy [Member] \| Minimum [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2021
Berkshire Hathaway Energy [Member] \| Railroad, Utilities and Energy [Member] \| Maximum [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2050
Berkshire Hathaway Energy Subsidiaries \| Railroad, Utilities and Energy [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 31,693				30,772
Weighted average interest rate, percentage	4.30%	4.30%	4.30%	4.30%
Berkshire Hathaway Energy Subsidiaries \| Railroad, Utilities and Energy [Member] \| Minimum [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Berkshire Hathaway Energy Subsidiaries \| Railroad, Utilities and Energy [Member] \| Maximum [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2064
Burlington Northern Santa Fe And Subsidiaries \| Railroad, Utilities and Energy [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 23,245				23,211
Weighted average interest rate, percentage	4.60%	4.60%	4.60%	4.60%
Burlington Northern Santa Fe And Subsidiaries \| Railroad, Utilities and Energy [Member] \| Minimum [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Burlington Northern Santa Fe And Subsidiaries \| Railroad, Utilities and Energy [Member] \| Maximum [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year	2097
Berkshire Hathaway Finance Corporation [Member] \| Insurance and Other [Member] \| Subsidiaries [Member] \| U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 8,829				8,679
Weighted average interest rate, percentage	4.10%	4.10%	4.10%	4.10%
Berkshire Hathaway Finance Corporation [Member] \| Insurance and Other [Member] \| Subsidiaries [Member] \| Great Britain Pound Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 2,218				2,274
Weighted average interest rate, percentage	2.50%	2.50%	2.50%	2.50%
Berkshire Hathaway Finance Corporation [Member] \| Insurance and Other [Member] \| Minimum [Member] \| Subsidiaries [Member] \| U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Berkshire Hathaway Finance Corporation [Member] \| Insurance and Other [Member] \| Minimum [Member] \| Subsidiaries [Member] \| Great Britain Pound Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2039
Berkshire Hathaway Finance Corporation [Member] \| Insurance and Other [Member] \| Maximum [Member] \| Subsidiaries [Member] \| U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2049
Berkshire Hathaway Finance Corporation [Member] \| Insurance and Other [Member] \| Maximum [Member] \| Subsidiaries [Member] \| Great Britain Pound Denominated [Member]
Debt Instrument [Line Items]
Debt maturity year	2059
Berkshire Hathaway Energy and Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Short-term borrowings	$ 2,400				$ 3,214
Short-term borrowings, weighted average interest rate	1.80%	1.80%	1.80%	1.80%