Description of Plan - Additional Information (Details) - EBP 001	12 Months Ended
Dec. 31, 2025 USD ($)
EBP, Description of Plan [Line Items]
Deferral rate	3.00%
Deferral rate increasing percentage	1.00%
Percentage of employee contribution	75.00%
Maximum contribution amount	$ 23,500
Percentage of employer contribution	100.00%
Employee benefit plan participant maximum annual catch up contribution amount	$ 7,500
Employee benefit plan maximum annual super catch-up contribution limit amount	3,750
Employee benefit plan discretionary profit sharing contributions	$ 3,034,249
Plan designated normal retirement age to withdrawals of employer contributions	55 years
Minimum required period of services for discretionary profit-sharing contribution to participants	1000 hours
Plan designated age to withdrawals of employer contributions if participant dies or disabled	59 years 6 months
Employee benefit plan minimum borrow amount	$ 1,000
Employee benefit plan maximum borrowing percentage	50.00%
Employee benefit plan highest outstanding note balance	$ 50,000
Maximum
EBP, Description of Plan [Line Items]
Deferral rate increasing percentage	6.00%
Percentage on employee eligible compensation	6.00%
Percentage of employer paid cash bonuses	100.00%

Employee benefit plan discretionary profit sharing contributions.

No definition available.

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Namespace Prefix:	brka_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Employee benefit plan maximum annual super catch up contribution limit amount.

+ References

No definition available.

+ Details

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Namespace Prefix:	brka_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Employee benefit plan participant contribution annual automatic increase in deferral rate

+ References

No definition available.

+ Details

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Namespace Prefix:	brka_
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Period Type:	duration

- Definition

Employee benefit plan participant employer paid cash bonuses percentage.

+ References

No definition available.

+ Details

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Namespace Prefix:	brka_
Data Type:	dtr-types:percentItemType
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Period Type:	duration

- Definition

Employee benefit plan participant maximum annual catch up contribution amount.

+ References

No definition available.

+ Details

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Namespace Prefix:	brka_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Minimum required period of services for discretionary profit-sharing contribution to participants.

+ References

No definition available.

+ Details

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Namespace Prefix:	brka_
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Balance Type:	na
Period Type:	duration

- Definition

Plan designated age to withdrawals of employer contributions if participant dies or disabled

+ References

No definition available.

+ Details

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Namespace Prefix:	brka_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Plan designated normal retirement age to withdrawals of employer contributions.

+ References

No definition available.

+ Details

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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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-SubTopic 205
-Topic 962
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of employer matching contribution on eligible participant contribution to employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Percentage of participant compensation eligible for employer matching contribution for participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of maximum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow to total participant account balance.

+ References

+ Details

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Period Type:	instant

- Definition

Amount of minimum account balance that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)) can borrow.

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of eligible compensation contributed for participant automatically enrolled in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)).

+ References

+ Details

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Namespace Prefix:	us-gaap-ebp_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of maximum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Percentage of maximum pretax annual compensation that participant in employee stock purchase, saving, or similar plan (employee benefit plan (EBP)), is permitted to contribute to total pretax annual compensation.

+ References

+ Details

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- Details

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- Details

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