Financing Receivable, before Allowance for Credit Loss, Number of Loans

No definition available.

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Namespace Prefix:	argo_
Data Type:	xbrli:integerItemType
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Period Type:	instant

- Definition

Percentage, before allowance for credit loss, of financing receivable to total financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (c)
-Publisher SEC

+ Details

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Balance Type:	na
Period Type:	instant

- 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

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Period Type:	duration

- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

+ Details

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

- Details

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Balance Type:
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- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=srt_ApartmentBuildingMember
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- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=srt_HotelMember
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- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=srt_IndustrialPropertyMember
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- Details

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- Details

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Investments - Schedule of Commercial Mortgage Loans (Details) $ in Millions	Mar. 31, 2024 USD ($) loan	Dec. 31, 2023 USD ($)	Dec. 31, 2023	Dec. 31, 2023 loan	Dec. 31, 2023 security
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 171.6	$ 144.8
Composition	100.00%		100.00%
Loan Count	30			28	28
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 1.7
Composition	1.00%
Loan Count \| loan	1
Apartments
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 76.1	76.1
Composition	44.30%		52.60%
Loan Count \| loan	16			16
Hotel
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 22.3	22.4
Composition	13.00%		15.40%
Loan Count \| loan	4			4
Industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 26.0	26.0
Composition	15.20%		18.00%
Loan Count \| loan	4			4
Office
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 25.9
Composition	15.10%
Loan Count \| loan	1
Retail
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage loans	$ 19.6	$ 20.3
Composition	11.40%		14.00%
Loan Count \| loan	4			4