Computation Of Earnings Per Share (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Earnings Per Share [Line Items]
Net income	$ 3,221	$ 7,618	$ 6,409	$ 19,034
Weighted average common shares outstanding:
Basic weighted average common shares outstanding	35,250,404	34,625,525	34,893,622	34,313,987
Effect of dilutive securities:
Warrants				214,871
Stock options	1,382,802	2,374,531	1,764,568	2,716,970
RSUs/RSAs	1,927,451	1,915,982	2,269,483	1,779,871
Diluted weighted average common shares outstanding	38,560,657	38,916,038	38,927,673	39,025,699
Earnings per common share:
Basic	$ 0.09	$ 0.22	$ 0.18	$ 0.55
Diluted	$ 0.08	$ 0.20	$ 0.16	$ 0.49