Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax [Line Items]
Effective income tax benefit rate	(4.70%)	(26.60%)	11.70%
Deferred tax assets, valuation allowance	$ 0	$ 0
Alternative minimum tax credit carry forward	10,957,000	10,868,000
Net operating loss carryforwards	3,205,000	1,934,000
Section 163(j) carryforward	8,075,000	3,135,000
Unrecognized tax benefits	0	0
Interest and penalties for uncertain tax positions	0	$ 0	$ 0
Liabilities for tax-related interest and penalties	$ 0
Global Indemnity Group Inc
Income Tax [Line Items]
Withholding tax paid in connection with the dividend payment			6,300,000
Dividends paid			$ 125,000,000
Withholding Tax			5.00%
UNITED STATES
Income Tax [Line Items]
Statutory income tax rates	35.00%
BERMUDA
Income Tax [Line Items]
Statutory income tax rates	0.00%
CAYMAN ISLANDS
Income Tax [Line Items]
Statutory income tax rates	0.00%
GIBRALTAR
Income Tax [Line Items]
Statutory income tax rates	0.00%
LUXEMBOURG
Income Tax [Line Items]
Statutory income tax rates	29.22%
IRELAND | Non Trading Income
Income Tax [Line Items]
Statutory income tax rates	25.00%
IRELAND | Capital Gain
Income Tax [Line Items]
Statutory income tax rates	33.00%
IRELAND | Trading Income
Income Tax [Line Items]
Statutory income tax rates	12.50%
BARBADOS | Minimum
Income Tax [Line Items]
Statutory income tax rates	0.25%
BARBADOS | Maximum
Income Tax [Line Items]
Statutory income tax rates	2.50%