Insurance Activity - Summary of Losses and Loss Adjustment Reserve Activity (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Liability For Unpaid Claims And Claims Adjustment Expense Net [Abstract]
Balance at beginning of period			$ 18,947	$ 44,314	$ 44,314
(Released) incurred - prior periods	$ (40)	$ 542	(358)	$ 4,531	3,281
Paid - prior periods			(12,007)		(28,648)
Total losses and loss adjustment reserves	$ 6,582		$ 6,582		$ 18,947