| 
           Stock Incentive Plan - Stock Options Outstanding (Details) (USD $)
  
         | 
        12 Months Ended | 
      
      
        | 
           Dec. 31, 2013 
         | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        4,573,378
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        3,067,015
 | 
      
      
        | 
           2000 Plan | Exercise Price $2.750 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 2.750
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        324,231
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        5 months 27 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 2.750
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        324,231
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 2.750
 | 
      
      
        | 
           2000 Plan | Exercise Price $3.000 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 3.000
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        13,600
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        1 year 26 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 3.000
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        13,600
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 3.000
 | 
      
      
        | 
           2000 Plan | Exercise Price $3.250 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 3.250
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        580,044
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        2 years 2 months 9 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 3.250
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        580,044
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 3.250
 | 
      
      
        | 
           2000 Plan | Exercise Price $3.410 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 3.410
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        442,462
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        3 years 18 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 3.410
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        442,462
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 3.410
 | 
      
      
        | 
           2000 Plan | Exercise Price $4.220 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 4.220
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        210,050
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        3 years 7 months 28 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 4.220
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        210,050
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 4.220
 | 
      
      
        | 
           2000 Plan | Exercise Price $6.055 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 6.055
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        966,400
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        5 years 6 months
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 6.055
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        839,100
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 6.055
 | 
      
      
        | 
           2000 Plan | Exercise Price $13.045 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 13.045
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        558,000
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        6 years 3 months 26 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 13.045
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        414,100
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 13.045
 | 
      
      
        | 
           2010 Plan | Exercise Price $7.150 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 7.150
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        30,000
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        9 years 3 months 22 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 7.150
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        0
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 7.150
 | 
      
      
        | 
           2010 Plan | Exercise Price $8.390 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 8.390
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        50,000
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        9 years 4 months 28 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 8.390
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        0
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 8.390
 | 
      
      
        | 
           2010 Plan | Exercise Price $8.480 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 8.480
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        100,000
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        9 years 8 months 9 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 8.480
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        0
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 8.480
 | 
      
      
        | 
           2010 Plan | Exercise Price $8.860 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 8.860
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        24,360
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        9 years 5 months 9 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 8.860
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        0
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 8.860
 | 
      
      
        | 
           2010 Plan | Exercise Price $9.450 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 9.450
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        374,000
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        9 years 6 months 22 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 9.450
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        0
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 9.450
 | 
      
      
        | 
           2010 Plan | Exercise Price $10.690 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 10.690
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        20,000
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        9 years 9 months 22 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 10.690
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        0
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 10.690
 | 
      
      
        | 
           2010 Plan | Exercise Price $10.750 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 10.750
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        50,000
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        8 years 4 months 28 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 10.750
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        10,000
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 10.750
 | 
      
      
        | 
           2010 Plan | Exercise Price $10.950 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 10.950
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        140,000
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        7 years 8 months 16 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 10.950
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        72,000
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 10.950
 | 
      
      
        | 
           2010 Plan | Exercise Price $11.630 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 11.630
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        155,093
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        8 years 5 months 16 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 11.630
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        36,028
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 11.630
 | 
      
      
        | 
           2010 Plan | Exercise Price $11.980 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 11.980
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        446,450
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        8 years 3 months 26 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 11.980
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        89,930
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 11.980
 | 
      
      
        | 
           2010 Plan | Exercise Price $14.810 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 14.810
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        60,000
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        7 years 4 months 24 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 14.810
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        24,000
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 14.810
 | 
      
      
        | 
           2010 Plan | Exercise Price $16.290 
         | 
         
 | 
      
      
        | Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] | 
         
 | 
      
      
        | Options Outstanding - Exercise Price | 
        $ 16.290
 | 
      
      
        | Outstanding Options - Number Outstanding (in shares) | 
        28,688
 | 
      
      
        | Outstanding Options - Weighted-Average Remaining Term | 
        7 years 26 days
 | 
      
      
        | Outstanding Options - Weighted-Average Exercise Price | 
        $ 16.290
 | 
      
      
        | Exercisable Options - Number Exercisable (in shares) | 
        11,470
 | 
      
      
        | Exercisable Options - Weighted-Average Exercise Price (in dollars per share) | 
        $ 16.290
 |