XML 49 R38.htm IDEA: XBRL DOCUMENT v3.4.0.3
Stock award plan (Details 2) - Unvested restricted stock awards and units
3 Months Ended
Mar. 31, 2016
$ / shares
shares
Number of Shares  
Balance at the beginning of the period (in shares) | shares 344,335
Granted (in shares) | shares 141,185
Forfeited (in shares) | shares (32,079)
Balance at the end of the period (in shares) | shares 453,441
Weighted Average Grant Date Fair Value  
Balance at the beginning of the period (in dollars per share) | $ / shares $ 10.85
Granted (in dollars per share) | $ / shares 30.86
Forfeited (in dollars per share) | $ / shares 16.26
Balance at the end of the period (in dollars per share) | $ / shares $ 16.70