Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity (Narrative) (Details)

v3.5.0.2
Stockholders' Equity (Narrative) (Details) - USD ($)
$ / shares in Units, $ in Millions
3 Months Ended
Jan. 08, 2016
Mar. 31, 2016
Mar. 31, 2015
2002 Stock Incentive Plan | Stock Options      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Shares available for future option grants   42,000  
Employee Stock Purchase Plan      
Employee Stock Purchase Plan      
Shares allowed to purchase in employee stock purchase plan   1,250  
Shares issued in period   0 0
Shares available for future purchases   72,367  
Employee Stock Purchase Plan | Stock Options      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Net proceeds from employee stock purchase plan   $ 1.0 $ 0.8
OMT, Inc.      
Employee Stock Purchase Plan      
Common stock issued in acquisition (shares) 793,070    
20-day volume-weighted average price of common stock issued in acquisition (usd per share) $ 107.66