XML 155 R144.htm IDEA: XBRL DOCUMENT
v3.24.0.1

Business segment data - Insurance premiums by geographic area (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Property/Casualty [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Premiums written | $ 80,339 | $ 70,688 | $ 65,275
Life/Health [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Premiums written | 5,093 | 5,767 | 6,276
United States [Member] | Property/Casualty [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Premiums written | 67,831 | 59,648 | 55,451
United States [Member] | Life/Health [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Premiums written | 1,285 | 2,107 | 2,143
Asia Pacific [Member] | Property/Casualty [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Premiums written | 5,306 | 4,699 | 3,822
Asia Pacific [Member] | Life/Health [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Premiums written | 1,760 | 1,704 | 2,030
Western Europe [Member] | Property/Casualty [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Premiums written | 5,014 | 4,901 | 4,613
Western Europe [Member] | Life/Health [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Premiums written | 1,323 | 1,235 | 1,298
All Other [Member] | Property/Casualty [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Premiums written | 2,188 | 1,440 | 1,389
All Other [Member] | Life/Health [Member] |  |  |
Segment Reporting Information [Line Items] |  |  |
Premiums written | $ 725 | $ 721 | $ 805

X
- Definition Amount, after premiums ceded to other entities and premiums assumed by the entity, of premiums written. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (c)(1) -SubTopic 605 -Topic 944 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479655/944-605-50-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -SubTopic 605 -Topic 944 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479655/944-605-50-1 + Details
Name: | us-gaap_PremiumsWrittenNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- 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. + Details
Name: | us-gaap_SegmentReportingInformationLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | srt_ProductOrServiceAxis=us-gaap_PropertyLiabilityAndCasualtyInsuranceSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ProductOrServiceAxis=brka_LifeAndHealthInsuranceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementGeographicalAxis=country_US
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementGeographicalAxis=srt_AsiaPacificMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementGeographicalAxis=brka_WesternEuropeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementGeographicalAxis=brka_AllOtherGeographicAreasMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |