XML 91 R77.htm IDEA: XBRL DOCUMENT
v3.24.0.1

Loans Receivable (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022
Loans Receivable [Line Items] |  |
Loans receivable | $ 201,271 | $ 193,002
Loans receivable | 198,244 | 187,981
Loans in nonaccrual status | 0 | 200
Real Estate Loans |  |
Loans Receivable [Line Items] |  |
Loans receivable | 200,381 | 173,616
Loans receivable | 197,354 | 168,595
Commercial |  |
Loans Receivable [Line Items] |  |
Loans receivable | 890 | 19,386
Loans receivable | $ 890 | $ 19,386
Loans receivable maturity term | 10 years |

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_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 16 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479319/326-20-50-16 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (3) -Publisher SEC Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (2) -Publisher SEC Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481962/310-10-50-7 + Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentNonaccrualStatus
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Publisher FASB -URI https://asc.fasb.org//310-10/tableOfContent + Details
Name: | us-gaap_LoansReceivableFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(1)(c)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1 + Details
Name: | us-gaap_MortgageLoansOnRealEstateCommercialAndConsumerNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Loans and Leases Receivable, Maturity Term + References No definition available. + Details
Name: | wrb_LoansandLeasesReceivableMaturityTerm
Namespace Prefix: | wrb_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |