Insurance Activity - Summary of Losses and Loss Adjustment Reserve Activity (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2014
Insurance [Abstract]
Balance at beginning of period	$ 44,314	$ 82,524	$ 142,119	$ 18,947
Incurred (released) - prior periods	3,281	(6,159)	30,111
Paid - prior periods	(28,648)	(32,051)	(89,706)
Total losses and loss adjustment reserves	$ 18,947	$ 44,314	$ 82,524