XML 76 R65.htm IDEA: XBRL DOCUMENT v3.19.1
Revenue recognition - Recognized revenue in the period (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Revenue from Contract with Customer [Abstract]    
Amounts included in contract liabilities at the beginning of the period $ 0 $ 0
Performance obligations satisfied in previous period 0 0
Performance obligations satisfied in current period   55,981
Total product revenue $ 53,054 $ 55,981