Collateral pledge as security for payments to be received under reinsurance contracts.

No definition available.

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- Definition

Line Of Credit Facility, Letter Of Credit Availability, Percentage

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No definition available.

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- Definition

Number of Letters of Credit

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No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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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

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The reporting currency-denominated liability value.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Long-term Debt - Additional Information (Detail) £ in Millions	1 Months Ended		12 Months Ended
	Nov. 30, 2021 USD ($)	Sep. 30, 2012 USD ($)	Dec. 31, 2022 USD ($) debtInstrument	Dec. 31, 2021 USD ($)	Dec. 20, 2022 USD ($)	Jun. 22, 2022 USD ($)	Nov. 30, 2021 GBP (£)	Nov. 02, 2018 USD ($)
Debt Instrument [Line Items]
Principal			$ 143,800,000	$ 143,800,000
Redemption price, percentage			100.00%
Floating rate loan stock denominated in Euros			$ 38,200,000	40,500,000
Amount of collateral under reinsurance agreement			1,299,300,000	1,085,500,000
Letter of Credit
Debt Instrument [Line Items]
Letter of credit facility amount outstanding			135,100,000
Amount of collateral under reinsurance agreement			$ 169,800,000
New Credit Agreement
Debt Instrument [Line Items]
Line of credit, maximum borrowing amount								$ 325,000,000
New Credit Agreement \| Term Loan
Debt Instrument [Line Items]
Principal								125,000,000
New Credit Agreement \| Revolving Credit Facility
Debt Instrument [Line Items]
Principal					$ 220,000,000			$ 200,000,000
New Credit Agreement \| Letter of Credit
Debt Instrument [Line Items]
Percentage of revolving credit facility allowed to be used for letters of credit			100.00%
Letter of credit facility amount outstanding			$ 300,000	$ 40,300,000
Reinsurance Credit Facilities, Secured Bilateral Line of Credit Facilities \| Letter of Credit
Debt Instrument [Line Items]
Letter of credit facility amount outstanding			205,000,000
Committed Secured Bilateral Facility \| Letter of Credit
Debt Instrument [Line Items]
Letter of credit facility amount outstanding			$ 50,200,000
Number of letters of credit \| debtInstrument			1
Debt instrument, term			1 year
Uncommitted Secured Bilateral Facility \| Letter of Credit
Debt Instrument [Line Items]
Letter of credit facility amount outstanding			$ 84,900,000
Number of letters of credit \| debtInstrument			2
Funds at Lloyd's Instrument \| Letter of Credit
Debt Instrument [Line Items]
Letter of credit facility amount outstanding	$ 35,100,000						£ 26
Debt instrument, term	1 year
Malta Sales Agreement \| Letter of Credit
Debt Instrument [Line Items]
Letter of credit facility amount outstanding						$ 50,000,000
Other Letters of Credit \| Letter of Credit
Debt Instrument [Line Items]
Letter of credit facility amount outstanding			$ 4,200,000
Senior unsecured fixed rate notes
Debt Instrument [Line Items]
Principal		$ 143,800,000
Debt instrument interest rate stated percentage		6.50%
Redemption price, percentage		100.00%
Junior subordinated debentures
Debt Instrument [Line Items]
Redemption price, percentage			100.00%	100.00%
Subordinated debentures
Debt Instrument [Line Items]
Principal			$ 91,800,000	$ 91,800,000
Debt instrument interest rate stated percentage			7.92%	3.35%
Unsecured debentures			$ 85,900,000	$ 85,500,000
Unsecured debt
Debt Instrument [Line Items]
Redemption price, percentage				100.00%