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

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

+ 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.

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-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.

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-SubTopic 10
-Section 50
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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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-SubTopic 10
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Notes payable and other borrowings - Narrative (Detail) € in Millions, £ in Millions, $ in Millions	1 Months Ended			6 Months Ended
	Jul. 31, 2019 USD ($)	Jun. 30, 2019 GBP (£)	Jan. 31, 2019 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 EUR (€)	Dec. 31, 2018 USD ($)
Insurance and Other [Member]
Debt Instrument [Line Items]
Carrying value of notes				$ 36,025			$ 34,975
Railroad, Utilities and Energy [Member]
Debt Instrument [Line Items]
Carrying value of notes				63,882			62,515
Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Subsidiaries Excluding Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Guarantee obligation				$ 1,500
Subsidiaries [Member] \| Insurance and Other [Member]
Debt Instrument [Line Items]
Weighted average interest rate, percentage				4.00%		4.00%
Subsidiaries [Member] \| Insurance and Other [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year				2019
Subsidiaries [Member] \| Insurance and Other [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year				2045
Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member] \| Debt Due 2029 To 2050 [Member]
Debt Instrument [Line Items]
Principal amount of debt issued				$ 3,400
Weighted average interest rate, percentage				3.90%		3.90%
Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member] \| Debt Due 2029 To 2050 [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year				2029
Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| Berkshire Hathaway Energy and Subsidiaries [Member] \| Debt Due 2029 To 2050 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year				2050
Senior Notes [Member] \| Subsidiaries [Member] \| Insurance and Other [Member] \| Berkshire Hathaway Finance Corporation [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| £		£ 1,750
Repayments of borrowings			$ 2,700
Senior Notes [Member] \| Subsidiaries [Member] \| Insurance and Other [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Notes Due 2049 at 4.25% [Member]
Debt Instrument [Line Items]
Principal amount of debt issued			$ 2,000
Debt instrument, interest rate, stated percentage			4.25%
Debt maturity year			2049
Senior Notes [Member] \| Subsidiaries [Member] \| Insurance and Other [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Notes Due 2039 at 2.375% [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| £		£ 1,000
Debt instrument, interest rate, stated percentage				2.375%		2.375%
Debt maturity year		2039
Senior Notes [Member] \| Subsidiaries [Member] \| Insurance and Other [Member] \| Berkshire Hathaway Finance Corporation [Member] \| Notes Due 2059 at 2.625% [Member]
Debt Instrument [Line Items]
Principal amount of debt issued \| £		£ 750
Debt instrument, interest rate, stated percentage				2.625%		2.625%
Debt maturity year		2059
Senior Unsecured Debenture [Member] \| Subsidiaries [Member] \| Railroad, Utilities and Energy [Member] \| BNSF [Member] \| Debentures Due in 2050 [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Principal amount of debt issued	$ 825
Debt instrument, interest rate, stated percentage	3.55%
Debt maturity year	2050
Euro Denominated [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member]
Debt Instrument [Line Items]
Carrying value of notes				$ 7,746		€ 6,850	$ 7,806
Weighted average interest rate, percentage				1.10%		1.10%
Euro Denominated [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt maturity year				2020
Euro Denominated [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt maturity year				2035
Euro Denominated [Member] \| Senior Notes [Member] \| Berkshire Hathaway Inc. (Parent) [Member] \| Insurance and Other [Member]
Debt Instrument [Line Items]
Gains attributable to changes in foreign currency exchange rates				$ 64	$ 219