Income Taxes [Line Items]

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Statutory rate on the foreign source insurance income and foreign tax credit.

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- Definition

Statutory tax rate

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- Definition

State and local deferred tax assets amounting to potential future tax benefits

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- Definition

The aggregate tax effects as of the balance sheet date of all future tax deductions arising from temporary differences between tax basis and generally accepted accounting principles basis recognition of assets, liabilities, revenues and expenses, which can only be deducted for tax purposes when permitted under enacted tax laws; net of deducting the allocated valuation allowance, if any, to reduce such amount to net realizable value.

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- Definition

The tax effect as of the balance sheet date of the amount of excess of tax deductions over gross income in a year which cannot be used on the tax return of a state or local jurisdiction in the current year but can be carried forward to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset.

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- Definition

The amount as of the balance sheet date of the estimated future tax effects attributable to undistributed earnings of subsidiaries and other recognized entities in countries outside the country of domicile which will increase future taxable income when such earnings are distributed into the country of domicile.

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- Definition

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

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- Definition

The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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State the expiration dates of the tax credit carryforward.

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- Definition

The earnings that is allocated to common stock and participating securities to the extent that each security may share in earnings as if all of the earnings for the period had been distributed.

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Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended		6 Months Ended
Income Taxes - Additional Information (Detail) (USD $)	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Dec. 31, 2010
Income Taxes [Line Items]
Undistributed earnings of non-U.S. subsidiaries			$ 8,700,000
Taxes payable on undistributed earnings	600,000		600,000
Deferred Tax Assets: State and Local	2,400,000		2,400,000		2,200,000
State and local net operating loss carry-forwards	1,400,000		1,400,000		1,400,000
Income tax (benefit) expense	5,032,000	8,223,000	539,000	14,568,000
Effective income tax rate	34.60%	30.20%	25.10%	28.80%
Net deferred tax asset	$ 6,871,000		$ 6,871,000		$ 15,141,000
Syndicate 1221 \| Minimum \| UNITED KINGDOM
Income Taxes [Line Items]
Foreign effective income tax rate			35.00%
UNITED KINGDOM
Income Taxes [Line Items]
Foreign effective income tax rate			35.00%
Corporate tax rate			28.00%
UNITED KINGDOM \| Expected Future Tax Rate
Income Taxes [Line Items]
Corporate tax rate			26.00%
Net investment income
Income Taxes [Line Items]
Effective income tax rate	28.70%	27.20%	28.60%	25.90%
State and Local Jurisdiction
Income Taxes [Line Items]
State and local tax carry-forwards expiration dates			The Company's state and local tax carry-forwards at June 30, 2011 expire from 2023 to 2025.