v3.2.0.727
Fair value measurement (Details) - Recurring basis - USD ($)
$ in Thousands
Jun. 30, 2015
Dec. 31, 2014
Level 1    
Assets:    
Money market accounts $ 2,230 $ 5,602
Total assets 2,230 5,602
Level 2    
Assets:    
Marketable securities   1,614
Total assets   1,614
Level 3    
Liabilities:    
Contingent consideration   131
Total liabilities   131
Total    
Assets:    
Money market accounts 2,230 5,602
Marketable securities   1,614
Total assets $ 2,230 7,216
Liabilities:    
Contingent consideration   131
Total liabilities   $ 131