Stock-Based Compensation - Summary of Stock Option Activity (Detail) - Stock Options [Member] - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Summary Of Stock Option Activities [Line Items]
Options Outstanding, Beginning balance, Shares			1,357,928
Options Outstanding, Granted			150,500
Options Outstanding, Exercised	0	(1,894)	(35,134)	(41,841)
Options Outstanding, Expired or cancelled			(110,683)
Options Outstanding, Forfeited			(72,820)
Options Outstanding, Ending balance, Shares	1,289,791		1,289,791
Options Exercisable, Ending balance, Shares	796,046		796,046
Options Outstanding, Beginning balance, Weighted Average Exercise Price			$ 7.81
Weighted Average Exercise Price, Granted			8.00
Weighted Average Exercise Price, Exercised			7.25
Weighted Average Exercise Price, Expired or Cancelled			9.00
Weighted Average Exercise Price, Forfeited			7.76
Options Outstanding, Ending balance, Weighted Average Exercise Price	$ 7.74		7.74
Options Outstanding, Exercisable at End of Year, Weighted Average Exercise Price	$ 7.96		$ 7.96