Organization and Summary of Significant Accounting Policies - Weighted Average Number of Shares Outstanding and Income Per Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Numerator for basic and diluted earnings per share:
Net income (loss)	$ 5,375	$ 5,114	$ 4,457	$ 3,298	$ 3,815	$ 3,677	$ 3,442	$ 3,804	$ 18,244	$ 14,738	$ (7,040)
Denominator:
Weighted average shares outstanding - basic									51,880	53,827	59,436
Dilutive effect of stock-based awards									2,272	896
Diluted weighted average shares outstanding									54,152	54,723	59,436
Anti-dilutive stock-based awards excluded									507	3,205	6,972
Net income (loss) per common share:
Basic	$ 0.10	$ 0.10	$ 0.09	$ 0.06	$ 0.07	$ 0.07	$ 0.06	$ 0.07	$ 0.35	$ 0.27	$ (0.12)
Diluted	$ 0.10	$ 0.10	$ 0.08	$ 0.06	$ 0.07	$ 0.07	$ 0.06	$ 0.07	$ 0.34	$ 0.27	$ (0.12)