Stock-Based Compensation - Summary of Retention Stock Option Activity (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	1 Months Ended	9 Months Ended
	Apr. 30, 2013	Sep. 30, 2013
Schedule Of Stock Options [Line Items]
Options outstanding, beginning balance, shares		1,099,106
Retention Stock Options Granted, shares		693,050
Options outstanding, ending balance, shares		1,531,184
Retention Stock Options outstanding, Exercisable, Ending balance, shares		823,251
Options outstanding, beginning balance, Weighted Average Exercise Price		$ 9.06
Retention Stock Options Granted, Weighted Average Exercise Price		$ 7.21
Options outstanding, ending balance, Weighted Average Exercise Price		$ 8.40
Retention Stock Options outstanding, Exercisable, Ending balance, Weighted Average Exercise Price		$ 9.46
Retention Stock Options [Member] | Executive Officer [Member]
Schedule Of Stock Options [Line Items]
Options outstanding, beginning balance, shares		0
Retention Stock Options Granted, shares	182,500	182,500
Options outstanding, ending balance, shares		182,500
Retention Stock Options outstanding, Exercisable, Ending balance, shares		0
Options outstanding, beginning balance, Weighted Average Exercise Price		$ 0.00
Retention Stock Options Granted, Weighted Average Exercise Price		$ 7.16
Options outstanding, ending balance, Weighted Average Exercise Price		$ 7.16
Retention Stock Options outstanding, Exercisable, Ending balance, Weighted Average Exercise Price		$ 0.00