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.

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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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- 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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- 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				9 Months Ended
	Jun. 30, 2022 USD ($)	May 31, 2022 USD ($)	Apr. 30, 2022 USD ($)	Jan. 31, 2022 USD ($)	Jan. 31, 2022 JPY (¥)	Sep. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2022 EUR (€)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 JPY (¥)	Sep. 30, 2022 EUR (€)	Sep. 30, 2022 GBP (£)	Dec. 31, 2021 USD ($)
Debt Instrument [Line Items]
Notes payable and other borrowings												¥ 914.0	€ 8,150	£ 1,750
Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued				$ 1,100	¥ 128.5
Weighted average interest rate, percentage				0.50%	0.50%
Minimum [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Debt maturity year				2027	2027
Maximum [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Debt maturity year				2052	2052
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings						$ 41,535				$ 41,535					$ 39,272
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Guarantee obligation						$ 3,700				$ 3,700
Insurance and Other [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage						4.10%				4.10%		4.10%	4.10%	4.10%
Notes payable and other borrowings						$ 4,328				$ 4,328					4,438
Insurance and Other [Member] \| Senior Notes [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Repayments of borrowings		$ 775
Insurance and Other [Member] \| Senior Notes [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Repayments of borrowings				$ 600
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						1,200			$ 264	$ 3,300	$ 939
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Principal amount of debt issued							$ 4,500
Weighted average interest rate, percentage							3.40%	3.40%
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2030 To 2034 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Principal amount of debt issued							$ 1,400	€ 1,250
Weighted average interest rate, percentage							1.80%	1.80%
Insurance and Other [Member] \| Minimum [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year										2022
Insurance and Other [Member] \| Minimum [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Debt maturity year							2027	2027
Insurance and Other [Member] \| Minimum [Member] \| Senior Notes [Member] \| Debt Due 2030 To 2034 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Debt maturity year							2030	2030
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] \| Debt Due 2027 To 2052 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Debt maturity year							2052	2052
Insurance and Other [Member] \| Maximum [Member] \| Senior Notes [Member] \| Debt Due 2030 To 2034 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Debt maturity year							2034	2034
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings						$ 74,961				$ 74,961					$ 74,990
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage						4.30%				4.30%		4.30%	4.30%	4.30%
Railroad, Utilities and Energy [Member] \| 4.6% Senior Notes Due [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Principal amount of debt issued			$ 1,000
Debt maturity year			2053
Debt instrument, interest rate, stated percentage			4.60%
Railroad, Utilities and Energy [Member] \| Term Debt [Member] \| Subsidiaries [Member] \| BNSF [Member]
Debt Instrument [Line Items]
Repayments of borrowings										$ 900
Railroad, Utilities and Energy [Member] \| Variable and Fixed Rate Term Debt [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Principal amount of debt issued										$ 1,300
Weighted average interest rate, percentage						3.90%				3.90%		3.90%	3.90%	3.90%
Railroad, Utilities and Energy [Member] \| Senior Unsecured Debenture [Member] \| 4.45% Debentures Due [Member] \| Subsidiaries [Member] \| BNSF [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 1,000
Debt maturity year	2053
Debt instrument, interest rate, stated percentage	4.45%
Railroad, Utilities and Energy [Member] \| Minimum [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Debt maturity year										2023
Railroad, Utilities and Energy [Member] \| Minimum [Member] \| Term Debt [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Debt maturity year										2024
Railroad, Utilities and Energy [Member] \| Maximum [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Debt maturity year										2053
Railroad, Utilities and Energy [Member] \| Maximum [Member] \| Term Debt [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Debt maturity year										2052