Employee Share-Based Compensation Plans - Summary of Stock Option Activity Under the Equity Plans (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Shares Under Options, Beginning Balance	4,109,537	3,730,573
Shares Under Options, Granted	412,170	938,757
Shares Under Options, Exercised	(250,123)	(99,541)
Shares Under Options, Forfeited or expired	(262,556)	(460,252)
Shares Under Options, Ending Balance	4,009,028	4,109,537
Weighted Average Exercise Price, Beginning Balance	$ 3.85	$ 3.88
Shares Under Options, Vested and expected to vest at December 31, 2013	3,737,491
Weighted Average Exercise Price, Granted	$ 4.18	$ 3.85
Shares Under Options, Exercisable at December 31, 2013	2,802,198
Weighted Average Exercise Price, Exercised	$ 3.39	$ 2.69
Weighted Average Exercise Price, Forfeited or expired	$ 4.30	$ 4.35
Weighted Average Exercise Price, Ending Balance	$ 3.89	$ 3.85
Weighted Average Exercise Price, Vested and expected to vest at December 31, 2013	$ 3.90
Weighted Average Exercise Price, Exercisable at December 31, 2013	$ 3.94
Weighted Average Remaining Contractual Term, Outstanding	3 years 10 months 13 days	4 years 5 months 1 day
Weighted Average Remaining Contractual Term, Vested and Expected to vest	3 years 9 months
Weighted Average Remaining Contractual Term, Exercisable	3 years 2 months 5 days
Aggregate Intrinsic Value, Outstanding	$ 12,933	$ 2,019
Aggregate Intrinsic Value, Vested and expected to vest	12,058
Aggregate Intrinsic Value, Exercisable	$ 9,043