Subsequent Events - Additional Information (Detail) (Subsequent Events, Global Indemnity Group Inc, American Reliable Insurance Company, USD $) In Millions, unless otherwise specified	0 Months Ended
	Oct. 16, 2014	Oct. 16, 2014
Subsequent Events | Global Indemnity Group Inc | American Reliable Insurance Company
Subsequent Event [Line Items]
Aggregate purchase price		$ 113.7
Date entered into the Stock Purchase Agreement	Oct. 16, 2014