Principles of Consolidation and Basis of Presentation - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012
Organization And Basis Of Presentation [Line Items]
Date of incorporation	Mar. 09, 2010
State of incorporation	Ireland
Kind of listing	A ordinary shares
Date of change in trading symbol	2010-07-06
Change in trading symbol	"INDM" to "GBLI."
Floating rate trust preferred securities issued	$ 30.0
Floating rate common securities issued	0.9
Junior subordinated debentures issued	$ 30.9