Stock-Based Compensation - Summary of Restricted Stock Units (Detail) (USD $)	3 Months Ended
	Mar. 31, 2014
Time-Based Restricted Stock Units [Member]
Performance Restricted Stock Units [Line Items]
Number of Shares, Beginning balance	85,270
Number of Shares, Granted	90,255
Number of Shares, Vested	(65,270)
Number of Shares, Forfeited or expired
Number of Shares, Ending balance	110,255
Weighted-Average Grant Date Fair Value, Beginning balance	$ 3.32
Weighted-Average Grant Date Fair Value, Granted	$ 7.04
Weighted-Average Grant Date Fair Value, Vested	$ 3.83
Weighted-Average Grant Date Fair Value, Forfeited or expired
Weighted-Average Grant Date Fair Value, Ending balance	$ 6.06
Performance-Based Restricted Stock Units [Member]
Performance Restricted Stock Units [Line Items]
Number of Shares, Beginning balance	313,000
Number of Shares, Granted
Number of Shares, Vested	(200,938)
Number of Shares, Forfeited or expired	(57,062)
Number of Shares, Ending balance	55,000
Weighted-Average Grant Date Fair Value, Beginning balance	$ 4.26
Weighted-Average Grant Date Fair Value, Granted
Weighted-Average Grant Date Fair Value, Vested	$ 3.87
Weighted-Average Grant Date Fair Value, Forfeited or expired	$ 4.04
Weighted-Average Grant Date Fair Value, Ending balance	$ 5.92