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

Debt maturing during period.

+ References

No definition available.

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- Definition

Reduction in short term borrowings.

+ 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
-SubTopic 210
-Section S99
-Paragraph 1
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- Definition

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

+ 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

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://fasb.org/us-gaap/role/ref/legacyRef
-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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
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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
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
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Notes payable and other borrowings - Narrative (Detail) € in Millions, £ in Millions, ¥ in Billions	1 Months Ended					3 Months Ended			9 Months Ended
	Apr. 30, 2020 USD ($)	Apr. 30, 2020 JPY (¥)	Mar. 31, 2020 USD ($)	Mar. 31, 2020 EUR (€)	Jan. 31, 2020 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2020 USD ($)	Mar. 31, 2020 EUR (€)	Mar. 31, 2020 JPY (¥)	Mar. 31, 2020 GBP (£)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Notes payable and other borrowings										€ 6,850	¥ 430.0	£ 1,750
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings			$ 37,486,000,000				$ 37,486,000,000						$ 37,590,000,000
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Guarantee obligation			$ 1,200,000,000				$ 1,200,000,000
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%
Insurance and Other [Member] \| Subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year							2020
Insurance and Other [Member] \| Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year							2045
Insurance and Other [Member] \| Senior Notes [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Gains attributable to changes in foreign currency exchange rates							$ 228,000,000	$ 170,000,000
Insurance and Other [Member] \| Senior Notes [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Repayments of borrowings					$ 350,000,000
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2025 at 0.0% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Repayments of borrowings \| €				€ 1,000
Principal amount of debt issued \| €				€ 1,000
Debt instrument, interest rate, stated percentage			0.00%				0.00%			0.00%	0.00%	0.00%
Debt maturity year			2025	2025
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2025 at 0.0% [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Forecast [Member]
Debt Instrument [Line Items]
Principal amount of debt issued						$ 1,600,000,000
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2023 To 2060 [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 1,800,000,000	¥ 195.5
Weighted average interest rate, percentage	1.07%	1.07%
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2023 To 2060 [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Minimum [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt maturity year	2023	2023
Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2023 To 2060 [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Maximum [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt maturity year	2060	2060
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2030 at 1.85% [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Principal amount of debt issued			$ 500,000,000
Debt instrument, interest rate, stated percentage			1.85%				1.85%			1.85%	1.85%	1.85%
Debt maturity year			2030	2030
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2030 at 1.85% [Member] \| Subsidiaries [Member] \| Forecast [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Debt maturing during period						$ 750,000,000			$ 550,000,000
Insurance and Other [Member] \| Other Senior Notes [Member] \| Notes Due 2025 at 0.0% [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Forecast [Member]
Debt Instrument [Line Items]
Principal amount of debt issued									0
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings			$ 66,747,000,000				$ 66,747,000,000						$ 65,778,000,000
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Repayments of borrowings							1,700,000,000
Reduction in short-term borrowings							1,100,000,000
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Forecast [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturing during period									800,000,000
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Subsequent Event [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 1,000,000,000.0
Railroad, Utilities and Energy [Member] \| Debt Due 2029 To 2050 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Principal amount of debt issued							$ 4,000,000,000.0
Weighted average interest rate, percentage			3.75%				3.75%			3.75%	3.75%	3.75%
Railroad, Utilities and Energy [Member] \| Debt Due 2029 To 2050 [Member] \| Subsidiaries [Member] \| Minimum [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year							2025
Railroad, Utilities and Energy [Member] \| Debt Due 2029 To 2050 [Member] \| Subsidiaries [Member] \| Maximum [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Debt maturity year							2050
Railroad, Utilities and Energy [Member] \| Bonds Due 2030 at 2.7% [Member] \| Subsidiaries [Member] \| Subsequent Event [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 400,000,000
Debt instrument, interest rate, stated percentage	2.70%	2.70%
Debt maturity year	2030	2030
Railroad, Utilities and Energy [Member] \| Bonds Due 2051 at 3.3% [Member] \| Subsidiaries [Member] \| Subsequent Event [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 600,000,000
Debt instrument, interest rate, stated percentage	3.30%	3.30%
Debt maturity year	2051	2051
Railroad, Utilities and Energy [Member] \| Senior Unsecured Debenture [Member] \| Debentures Due 2051 [Member] \| Subsidiaries [Member] \| Forecast [Member] \| BNSF [Member]
Debt Instrument [Line Items]
Debt maturing during period									$ 450,000,000
Railroad, Utilities and Energy [Member] \| Senior Unsecured Debenture [Member] \| Debentures Due 2051 [Member] \| Subsidiaries [Member] \| Subsequent Event [Member] \| BNSF [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 575,000,000
Debt instrument, interest rate, stated percentage	3.05%	3.05%
Debt maturity year	2051	2051