Year the debt matures, in CCYY format.

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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

The unpaid balance of subsidiary debt that the parent entity has guaranteed full payment of present and future obligations when due.

+ References

No definition available.

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- Definition

Aggregate amount of short-term and long-term debt maturing or scheduled to be repaid within the next twelve months following the date of the latest balance sheet presented in the financial statements.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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- Definition

Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

+ References

No definition available.

+ Details

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Note to Condensed Financial Information - Narrative (Detail) € in Millions, $ in Millions, ¥ in Billions	1 Months Ended			12 Months Ended
	Apr. 30, 2020 USD ($)	Apr. 30, 2020 JPY (¥)	Mar. 31, 2020 EUR (€)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 EUR (€)	Dec. 31, 2020 JPY (¥)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2020 EUR (€)	Dec. 31, 2020 JPY (¥)
Condensed Financial Statements, Captions [Line Items]
Debt maturities: 2021				$ 9,398
Debt maturities: 2022				4,998
Debt maturities: 2023				10,813
Debt maturities: 2024				6,308
Debt maturities: 2025				6,594
Insurance and Other [Member]
Condensed Financial Statements, Captions [Line Items]
Debt maturities: 2021				4,354
Debt maturities: 2022				1,593
Debt maturities: 2023				6,021
Debt maturities: 2024				2,343
Debt maturities: 2025				2,817
Berkshire Hathaway Inc. (Parent) [Member]
Condensed Financial Statements, Captions [Line Items]
Repayments of borrowings				1,151			$ 758	$ 1,563
Principal amount of debt issued									€ 6,850	¥ 625.5
Debt maturities: 2021				2,172
Debt maturities: 2022				600
Debt maturities: 2023				4,633
Debt maturities: 2024				2,272
Debt maturities: 2025				1,801
Guarantees of subsidiary debt				14,400
Berkshire Hathaway Inc. (Parent) [Member] \| Berkshire Hathaway Finance Corporation [Member]
Condensed Financial Statements, Captions [Line Items]
Guarantees of subsidiary debt				$ 13,100
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2025 at 0.0% [Member]
Condensed Financial Statements, Captions [Line Items]
Repayments of borrowings \| €			€ 1,000		€ 1,000
Principal amount of debt issued \| €			€ 1,000		€ 1,000
Debt instrument, interest rate, stated percentage			0.00%	0.00%					0.00%	0.00%
Debt maturity year			2025	2025	2025	2025
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2023 To 2060 [Member]
Condensed Financial Statements, Captions [Line Items]
Principal amount of debt issued	$ 1,800	¥ 195.5		$ 1,800		¥ 195.5
Weighted average interest rate, percentage	1.07%	1.07%		1.07%					1.07%	1.07%
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2023 To 2060 [Member] \| Minimum [Member]
Condensed Financial Statements, Captions [Line Items]
Debt maturity year	2023	2023		2023	2023	2023
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Senior Notes [Member] \| Debt Due 2023 To 2060 [Member] \| Maximum [Member]
Condensed Financial Statements, Captions [Line Items]
Debt maturity year	2060	2060		2060	2060	2060
Berkshire Hathaway Inc. (Parent) [Member] \| The Kraft Heinz Company [Member]
Condensed Financial Statements, Captions [Line Items]
Equity method investment ownership percentage after transactions				26.60%	26.60%	26.60%