Consolidated Statements Of Redeemable Convertible Preferred Stock And Stockholders' Equity (USD $)
In Thousands
Total
Redeemable Convertible Preferred Stock [Member]
Common Stock [Member]
Additional Paid-In Capital [Member]
Retained Earnings (Accumulated Deficit) [Member]
Accumulated Other Comprehensive Income (Loss) [Member]
Balance at Dec. 31, 2010 $ 10,707 $ 62,793 $ 1 $ 51 $ 10,655 $ 0
Balance, shares at Dec. 31, 2010   26,230 10,944      
Net income 29,132          
Unrealized gain (loss) on available-for-sale securities, net of tax (23)         (23)
Issuance of common stock in May 2011 initial public offering, shares     9,065      
Issuance of common stock in May 2011 initial public offering 157,257   1 157,256    
Issuance of common stock in September 2011 follow on offering, shares     1,400      
Issuance of common stock in September 2011 follow on offering 26,855   0 26,855    
Issuance of common stock upon exercise of stock options, vesting of restricted stock units and other common stock issuances, shares     1,269      
Issuance of common stock upon exercise of stock options, vesting of restricted stock units and other common stock issuances 2,835   0 2,835    
Issuance of restricted stock upon early exercise of options, shares     237      
Conversion of preferred stock into shares of common stock, shares   (26,230) (26,230)      
Conversion of preferred stock into shares of common stock 62,793 (62,793) 3 62,790    
Vesting of stock options early exercised 102   0 102    
Stock-based compensation 7,106     7,106    
Tax benefit of equity award deductions 2,302     2,302    
Other 18     18    
Balance at Dec. 31, 2011 299,084   5 259,315 39,787 (23)
Balance, shares at Dec. 31, 2011     49,145      
Net income 38,957          
Unrealized gain (loss) on available-for-sale securities, net of tax 3         3
Issuance of common stock upon exercise of stock options, vesting of restricted stock units and other common stock issuances, shares     1,869      
Issuance of common stock upon exercise of stock options, vesting of restricted stock units and other common stock issuances 3,154   0 3,154    
Issuance of restricted stock upon early exercise of options, shares     70      
Vesting of stock options early exercised 105   0 105    
Stock-based compensation 10,644     10,644    
Tax benefit of equity award deductions 8,317     8,317    
Other (5)     (5)    
Balance at Dec. 31, 2012 360,259   5 281,530 78,744 (20)
Balance, shares at Dec. 31, 2012     51,084      
Net income 40,783          
Unrealized gain (loss) on available-for-sale securities, net of tax 68         68
Issuance of common stock upon exercise of stock options, vesting of restricted stock units and other common stock issuances, shares 1,244   1,618      
Issuance of common stock upon exercise of stock options, vesting of restricted stock units and other common stock issuances 5,223   0 5,223    
Vesting of stock options early exercised 66   0 66    
Stock-based compensation 16,192     16,192    
Tax benefit of equity award deductions 3,088     3,088    
Repurchase of common stock, shares (10)          
Tax withholdings related to net share settlements of restricted stock units (756)     (756)    
Balance at Dec. 31, 2013 $ 424,923   $ 5 $ 305,343 $ 119,527 $ 48
Balance, shares at Dec. 31, 2013     52,692