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
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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
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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

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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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
-Topic 830
-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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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

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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Subparagraph (b)
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Notes payable and other borrowings - Narrative (Detail) € in Millions, £ in Millions, $ in Millions, ¥ in Billions	1 Months Ended		12 Months Ended
	Jan. 31, 2022 USD ($)	Jan. 31, 2022 JPY (¥)	Dec. 31, 2021 USD ($)	Dec. 31, 2021 EUR (€)	Dec. 31, 2021 JPY (¥)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2021 EUR (€)	Dec. 31, 2021 JPY (¥)	Dec. 31, 2021 GBP (£)
Debt Instrument [Line Items]
Notes payable and other borrowings								€ 6,900	¥ 785.5	£ 1,750
Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Repayments of borrowings			$ 2,167			$ 1,151	$ 758
Notes payable and other borrowings			21,409			22,665
Gain (loss) attributable to changes in foreign currency exchange rates			1,281			(970)	193
Line Of Credit [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Unused lines of credit available			10,400
Line Of Credit [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Unused lines of credit available			8,700
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings			39,272			41,522
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Guarantee obligation			$ 3,800
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Repayments of borrowings	$ 600
Insurance and Other [Member] \| Subsidiaries [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage			4.00%					4.00%	4.00%	4.00%
Insurance and Other [Member] \| Subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year			2022	2022	2022
Insurance and Other [Member] \| Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year			2045	2045	2045
Insurance and Other [Member] \| Senior Notes [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Repayments of borrowings			$ 750
Insurance and Other [Member] \| Senior Notes [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Repayments of borrowings			1,500	€ 550
Gain (loss) attributable to changes in foreign currency exchange rates			$ 1,300			(1,000)	$ 192
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2041 at 0.5% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| €				€ 600
Debt instrument, interest rate, stated percentage			0.50%					0.50%	0.50%	0.50%
Debt maturity year			2041	2041	2041
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2026 To 2041 [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%	0.50%	0.50%
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2026 To 2041 [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year			2026	2026	2026
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2026 To 2041 [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year			2041	2041	2041
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2027 To 2052 [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Subsequent Event [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] \| Subsequent Event [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] \| Subsequent Event [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year	2052	2052
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]
Principal amount of debt issued			$ 750
Debt instrument, interest rate, stated percentage			2.50%					2.50%	2.50%	2.50%
Debt maturity year			2051	2051	2051
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings			$ 74,990			$ 75,373
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Repayments of borrowings			2,500
Railroad, Utilities and Energy [Member] \| Debt Due 2028 To 2052 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Principal amount of debt issued			$ 2,200
Weighted average interest rate, percentage			3.20%					3.20%	3.20%	3.20%
Railroad, Utilities and Energy [Member] \| Debt Due 2028 To 2052 [Member] \| Subsidiaries [Member] \| Minimum [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year			2028	2028	2028
Railroad, Utilities and Energy [Member] \| Debt Due 2028 To 2052 [Member] \| Subsidiaries [Member] \| Maximum [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year			2052	2052	2052
Railroad, Utilities and Energy [Member] \| Senior Unsecured Debenture [Member] \| Subsidiaries [Member] \| BNSF [Member]
Debt Instrument [Line Items]
Repayments of borrowings			$ 1,540
Principal amount of debt issued			$ 1,550
Weighted average interest rate, percentage			3.10%					3.10%	3.10%	3.10%
Railroad, Utilities and Energy [Member] \| Senior Unsecured Debenture [Member] \| Subsidiaries [Member] \| Minimum [Member] \| BNSF [Member]
Debt Instrument [Line Items]
Debt maturity year			2051	2051	2051
Railroad, Utilities and Energy [Member] \| Senior Unsecured Debenture [Member] \| Subsidiaries [Member] \| Maximum [Member] \| BNSF [Member]
Debt Instrument [Line Items]
Debt maturity year			2052	2052	2052