Year the debt matures, in CCYY format.

No definition available.

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- Definition

The principal amount of new debt issued during the period, excluding premium or discount, if any.

+ References

No definition available.

+ Details

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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
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-Paragraph 1
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (b)
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-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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.

+ Details

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Period Type:	instant

- Definition

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
-Paragraph 1
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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
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Notes payable and other borrowings - Narrative (Detail) € in Millions, £ in Millions, $ in Millions, ¥ in Billions	1 Months Ended		3 Months Ended		6 Months Ended
	Apr. 30, 2021 USD ($)	Apr. 30, 2021 JPY (¥)	Mar. 31, 2021 USD ($)	Mar. 31, 2021 EUR (€)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 EUR (€)	Jun. 30, 2021 JPY (¥)	Jun. 30, 2021 GBP (£)	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Notes payable and other borrowings							€ 6,900	¥ 785.5	£ 1,750
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings					$ 40,561					$ 41,522
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Guarantee obligation					$ 4,000
Insurance and Other [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage					4.10%		4.10%	4.10%	4.10%
Insurance and Other [Member] \| Senior Notes [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Gains (loss) attributable to changes in foreign currency exchange rates					$ 675	$ 102
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2041 at 0.5% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Repayments of borrowings			$ 1,000	€ 550
Principal amount of debt issued \| €				€ 600
Debt instrument, interest rate, stated percentage			0.50%	0.50%
Debt maturity year			2041	2041
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due Ranging From 2026-2041 at 0.5% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 1,500	¥ 160.0
Weighted average interest rate, percentage	0.50%	0.50%
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2051 at 2.5% [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Repayments of borrowings					750
Principal amount of debt issued					$ 750
Debt instrument, interest rate, stated percentage					2.50%		2.50%	2.50%	2.50%
Debt maturity year					2051
Insurance and Other [Member] \| Minimum [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year					2021
Insurance and Other [Member] \| Minimum [Member] \| Senior Notes [Member] \| Notes Due Ranging From 2026-2041 at 0.5% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Debt maturity year	2026	2026
Insurance and Other [Member] \| Maximum [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year					2045
Insurance and Other [Member] \| Maximum [Member] \| Senior Notes [Member] \| Notes Due Ranging From 2026-2041 at 0.5% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Debt maturity year	2041	2041
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings					$ 74,662					$ 75,373
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Repayments of borrowings					1,700
Railroad, Utilities and Energy [Member] \| Notes Due 2051 at 3.4% [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 550
Debt instrument, interest rate, stated percentage	3.40%	3.40%
Debt maturity year	2051	2051
Railroad, Utilities and Energy [Member] \| Senior Unsecured Debenture [Member] \| Debentures Due 2051 [Member] \| Subsidiaries [Member] \| BNSF [Member]
Debt Instrument [Line Items]
Repayments of borrowings					$ 886
Principal amount of debt issued	$ 925
Debt instrument, interest rate, stated percentage	3.30%	3.30%
Debt maturity year	2051	2051