Net Income per Share - Earnings Attributable to Common Shareholders and Weighted Average Common Shares Outstanding (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Numerator:
Consolidated net income	$ 17,088	$ 35,061	$ 17,876
Less: Net income attributable to noncontrolling interest	(505)	(5,740)	(4,934)
Earnings available for diluted earnings per share	16,583	29,321	12,942
Less: Undistributed net income allocated to participating securities	(3,018)	(585)	0
Earnings available to common shareholders for basic earnings per share	$ 13,565	$ 28,736	$ 12,942
Weighted average common shares outstanding - basic	35,317	35,365	35,214
Weighted average common shares upon conversion of participating securities	7,857	835	0
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	422	613	268
Weighted average common shares outstanding - diluted	43,596	36,813	35,482
Anti-dilutive awards excluded from diluted weighted average shares outstanding	2,238	1,803	2,713