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
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13,16)
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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
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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Balance Type:	na
Period Type:	instant

- 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
-Section 50
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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

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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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 Millions, ¥ in Billions	1 Months Ended			12 Months Ended
	Jan. 31, 2020 USD ($)	Sep. 30, 2019 JPY (¥)	Jul. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 GBP (£)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2019 JPY (¥)	Dec. 31, 2019 GBP (£)	Dec. 31, 2019 EUR (€)
Debt Instrument [Line Items]
Notes payable and other borrowings								¥ 430.0	£ 1,750	€ 6,850
Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Repayments of borrowings				$ 758		$ 1,563	$ 1,145
Notes payable and other borrowings				19,903		16,871
Gain (loss) attributable to changes in foreign currency exchange rates				193		366	(1,008)
Insurance and Other [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings				37,590		34,975
Insurance and Other [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Guarantee obligation				$ 1,200
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				2020	2020
Insurance and Other [Member] \| Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year				2045	2045
Insurance and Other [Member] \| Senior Notes [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| ¥		¥ 430.0
Gain (loss) attributable to changes in foreign currency exchange rates				$ 192		366	$ (990)
Insurance and Other [Member] \| Senior Notes [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| £					£ 1,750
Repayments of borrowings				3,950
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2024 at 0.17% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| ¥		¥ 108.5
Debt instrument, interest rate, stated percentage		0.17%
Debt maturity year		2024
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2026 at 0.27% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| ¥		¥ 61.0
Debt instrument, interest rate, stated percentage		0.27%
Debt maturity year		2026
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2029 at 0.44% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| ¥		¥ 146.5
Debt instrument, interest rate, stated percentage		0.44%
Debt maturity year		2029
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2034 at 0.787% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| ¥		¥ 19.0
Debt instrument, interest rate, stated percentage		0.787%
Debt maturity year		2034
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2039 at 0.965% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| ¥		¥ 59.0
Debt instrument, interest rate, stated percentage		0.965%
Debt maturity year		2039
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2049 at 1.108% [Member] \| Berkshire Hathaway Inc. (Parent) [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| ¥		¥ 36.0
Debt instrument, interest rate, stated percentage		1.108%
Debt maturity year		2049
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2049 at 4.25% [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Principal amount of debt issued				$ 2,000
Debt instrument, interest rate, stated percentage				4.25%				4.25%	4.25%	4.25%
Debt maturity year				2049	2049
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2039 at 2.375% [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| £					£ 1,000
Debt instrument, interest rate, stated percentage				2.375%				2.375%	2.375%	2.375%
Debt maturity year				2039	2039
Insurance and Other [Member] \| Senior Notes [Member] \| Notes Due 2059 at 2.625% [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| £					£ 750
Debt instrument, interest rate, stated percentage				2.625%				2.625%	2.625%	2.625%
Debt maturity year				2059	2059
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Notes payable and other borrowings				$ 65,778		$ 62,515
Railroad, Utilities and Energy [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 725
Railroad, Utilities and Energy [Member] \| Debt Due 2029 To 2059 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member]
Debt Instrument [Line Items]
Principal amount of debt issued				$ 4,600
Weighted average interest rate, percentage				3.60%				3.60%	3.60%	3.60%
Railroad, Utilities and Energy [Member] \| Debt Due 2029 To 2059 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year				2029	2029
Railroad, Utilities and Energy [Member] \| Debt Due 2029 To 2059 [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year				2059	2059
Railroad, Utilities and Energy [Member] \| Notes Due 2030 at 2.4% [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 425
Debt instrument, interest rate, stated percentage	2.40%
Debt maturity year	2030
Railroad, Utilities and Energy [Member] \| Notes Due 2050 at 3.125% [Member] \| Subsidiaries [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 300
Debt instrument, interest rate, stated percentage	3.125%
Debt maturity year	2050
Railroad, Utilities and Energy [Member] \| Senior Unsecured Debenture [Member] \| Debentures Due 2048 [Member] \| Subsidiaries [Member] \| BNSF [Member]
Debt Instrument [Line Items]
Principal amount of debt issued			$ 825
Debt instrument, interest rate, stated percentage			3.55%
Debt maturity year			2050