Annual report pursuant to Section 13 and 15(d)

Stockholders' Equity and Stock Based Compensation - Plans (Details)

v3.6.0.2
Stockholders' Equity and Stock Based Compensation - Plans (Details)
12 Months Ended
Mar. 01, 2002
shares
Dec. 31, 2016
installment
shares
Dec. 31, 2015
installment
shares
Dec. 31, 2014
installment
shares
Jun. 06, 2012
shares
Jun. 14, 2006
shares
May 07, 1998
shares
1995 Plan              
Stock-based compensation              
Number of shares of common stock initially available for award             1,137,500
Expiration period   10 years          
Options reserved for future issuance (in shares)   0          
1995 Director Plan              
Stock-based compensation              
Number of shares of common stock initially available for award             187,500
Expiration period   10 years          
Vesting period   5 years          
Period from grant date after which awards begin to vest   1 year          
Options reserved for future issuance (in shares)   0          
1995 Director Plan | Vesting of awards in equal quarterly installments from expiration of one year from the date of grant              
Stock-based compensation              
Percentage of award vesting   5.00%          
1995 Director Plan | Vesting of awards in one year from the date of grant              
Stock-based compensation              
Percentage of award vesting   20.00%          
1995 Plan and 1995 Director Plan              
Stock-based compensation              
Options surrendered (in shares) 303,550            
2006 Plan              
Stock-based compensation              
Number of shares of common stock initially available for award           800,000  
Options reserved for future issuance (in shares)   0          
2012 Plan              
Stock-based compensation              
Number of shares of common stock initially available for award         600,000    
Options reserved for future issuance (in shares)   303,061          
2012 Plan | Restricted stock              
Stock-based compensation              
Granted (in shares)   171,252 44,000 98,689      
Number of equal quarterly installments for vesting of awards | installment     16        
Forfeited (in shares)   7,167 4,465 34,487      
2012 Plan | Restricted stock | Minimum              
Stock-based compensation              
Number of equal quarterly installments for vesting of awards | installment   1   1      
2012 Plan | Restricted stock | Maximum              
Stock-based compensation              
Number of equal quarterly installments for vesting of awards | installment   20   20      
2006 Plan and 2012 Plan | Restricted stock              
Stock-based compensation              
Granted (in shares)   171,252 44,000 98,689      
Forfeited (in shares)   7,167 4,465 34,487