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

Other subsidiary and short-term subsidiary borrowings.

+ References

No definition available.

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- Definition

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

+ References

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-Topic 942
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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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-Subparagraph (b)
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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

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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-Name Accounting Standards Codification
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-Paragraph 2
-Subparagraph (bbb)(2)
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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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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.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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-Publisher FASB
-Name Accounting Standards Codification
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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.

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-Publisher FASB
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Notes payable and other borrowings - Narrative (Detail) € in Millions, £ in Millions, $ in Millions, ¥ in Billions		1 Months Ended					2 Months Ended		3 Months Ended		12 Months Ended
	Jan. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2022 JPY (¥)	Jun. 30, 2022 USD ($)	Jan. 31, 2022 USD ($)	Jan. 31, 2022 JPY (¥)	Apr. 30, 2023 USD ($)	Feb. 28, 2023 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2022 EUR (€)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2022 JPY (¥)	Dec. 31, 2022 EUR (€)	Dec. 31, 2022 GBP (£)
Debt Instrument [Line Items]
Notes payable and other borrowings														¥ 1,029.0	€ 8,150	£ 1,750
Gain (loss) attributable to changes in foreign currency exchange rates											$ 2,148	$ 1,433	$ (1,074)
Alleghany Corporation and its Subsidiaries [Member]
Debt Instrument [Line Items]
Other subsidiary and short-term subsidiary borrowings		$ 2,300									2,300
Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Repayments of borrowings											602	2,167	1,151
Notes payable and other borrowings		21,393									21,393	21,409
Gain (loss) attributable to changes in foreign currency exchange rates											1,401	1,281	(970)
Line Of Credit [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Unused lines of credit available		11,100									11,100
Line Of Credit [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Unused lines of credit available		9,100									9,100
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings		46,538									46,538	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] \| Berkshire Hathaway Inc. (Parent) [Member] \| Subsequent Event [Member] \| Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Guarantee obligation	$ 1,000
Debt maturity period	Jan. 31, 2023
Insurance and Other [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage		4.30%									4.30%			4.30%	4.30%	4.30%
Notes payable and other borrowings		$ 5,967									$ 5,967	4,438
Insurance and Other [Member] \| Subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year											2023
Insurance and Other [Member] \| Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year											2051
Insurance and Other [Member] \| Senior Notes [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Gain (loss) attributable to changes in foreign currency exchange rates											$ 1,700	1,300	$ (1,000)
Insurance and Other [Member] \| Senior Notes [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Forecast [Member]
Debt Instrument [Line Items]
Repayments of borrowings							$ 3,200
Insurance and Other [Member] \| Senior Notes [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Repayments of borrowings								$ 1,100
Insurance and Other [Member] \| 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%
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year					2027	2027
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year					2052	2052
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 2027 To 2052 [Member] \| Subsidiaries [Member] \| Minimum [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Debt maturity year									2027	2027
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Subsidiaries [Member] \| Maximum [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Debt maturity year									2052	2052
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2025 To 2052 [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued		$ 840	¥ 115.0
Weighted average interest rate, percentage		1.10%									1.10%			1.10%	1.10%	1.10%
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2025 To 2052 [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year		2025	2025
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2025 To 2052 [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year		2052	2052
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] \| Senior Notes [Member] \| Debt Due 2030 To 2034 [Member] \| Subsidiaries [Member] \| Minimum [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Debt maturity year									2030	2030
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2030 To 2034 [Member] \| Subsidiaries [Member] \| Maximum [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		$ 76,206									$ 76,206	$ 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] \| Subsidiaries [Member] \| Minimum [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Debt maturity year											2023
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Maximum [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Debt maturity year											2053
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 instrument, interest rate, stated percentage		4.60%									4.60%			4.60%	4.60%	4.60%
Debt maturity year											2053
Railroad, Utilities and Energy [Member] \| Term Loan [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Principal amount of debt issued											$ 3,000
Weighted average interest rate, percentage		5.20%									5.20%			5.20%	5.20%	5.20%
Railroad, Utilities and Energy [Member] \| Term Loan [Member] \| Subsidiaries [Member] \| Minimum [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Debt maturity year											2024
Railroad, Utilities and Energy [Member] \| Term Loan [Member] \| Subsidiaries [Member] \| Maximum [Member] \| Berkshire Hathaway Energy [Member]
Debt Instrument [Line Items]
Debt maturity year											2053
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 instrument, interest rate, stated percentage				4.45%
Railroad, Utilities and Energy [Member] \| Senior Unsecured Debenture [Member] \| 4.45% Debentures Due [Member] \| Subsidiaries [Member] \| Minimum [Member] \| BNSF [Member]
Debt Instrument [Line Items]
Debt maturity year				2053