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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Period Type:	instant

- 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.

+ References

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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).

+ 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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Notes payable and other borrowings (Detail) € in Millions, £ in Millions, $ in Millions, ¥ in Billions	9 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2019 JPY (¥)	Sep. 30, 2019 GBP (£)	Sep. 30, 2019 EUR (€)	Dec. 31, 2018 USD ($)
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 37,176				$ 34,975
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings		¥ 430	£ 1,750	€ 6,850
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| U.S. Dollar Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 8,321				9,065
Weighted average interest rate, percentage	3.20%	3.20%	3.20%	3.20%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| U.S. Dollar Denominated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2019
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| U.S. Dollar Denominated [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2047
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Euro Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 7,422				7,806
Weighted average interest rate, percentage	1.10%	1.10%	1.10%	1.10%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Euro Denominated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Euro Denominated [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2035
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Japanese Yen Denominated [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 3,962
Weighted average interest rate, percentage	0.50%	0.50%	0.50%	0.50%
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Japanese Yen Denominated [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2024
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Japanese Yen Denominated [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2049
Insurance and Other [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Other borrowings	$ 5,304				5,597
Short-term borrowings	$ 1,380				1,857
Weighted average interest rate, percentage	4.00%	4.00%	4.00%	4.00%
Short-term borrowings, weighted average interest rate	4.10%	4.10%	4.10%	4.10%
Insurance and Other [Member] \| Subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2019
Insurance and Other [Member] \| Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2045
Insurance and Other [Member] \| Subsidiaries [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%
Insurance and Other [Member] \| Subsidiaries [Member] \| U.S. Dollar Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Insurance and Other [Member] \| Subsidiaries [Member] \| U.S. Dollar Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2049
Insurance and Other [Member] \| Subsidiaries [Member] \| Great Britain Pound Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 2,108
Weighted average interest rate, percentage	2.50%	2.50%	2.50%	2.50%
Insurance and Other [Member] \| Subsidiaries [Member] \| Great Britain Pound Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2039
Insurance and Other [Member] \| Subsidiaries [Member] \| Great Britain Pound Denominated [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2059
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 65,018				62,515
Railroad, Utilities and Energy [Member] \| Subsidiaries [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	$ 8,580				8,577
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2020
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2049
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy Subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 29,329				28,196
Weighted average interest rate, percentage	4.50%	4.50%	4.50%	4.50%
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy Subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2019
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2064
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Short-term borrowings	$ 3,119				2,516
Short-term borrowings, weighted average interest rate	2.80%	2.80%	2.80%	2.80%
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Burlington Northern Santa Fe and subsidiaries [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings	$ 23,990				$ 23,226
Weighted average interest rate, percentage	4.60%	4.60%	4.60%	4.60%
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Burlington Northern Santa Fe and subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year	2019
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Burlington Northern Santa Fe and subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2097