Revenue recognition - Disaggregated revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenue recognition
Revenue	$ 15,727	$ 12,337
Product revenue
Revenue recognition
Revenue	9,833	9,547
Product revenue | NA
Revenue recognition
Revenue	4,677	5,016
Product revenue | EMEA
Revenue recognition
Revenue	3,430	3,233
Product revenue | Asia Pacific
Revenue recognition
Revenue	1,726	1,298
Instruments
Revenue recognition
Revenue	3,688	3,416
Instruments | NA
Revenue recognition
Revenue	1,753	1,397
Instruments | EMEA
Revenue recognition
Revenue	726	1,145
Instruments | Asia Pacific
Revenue recognition
Revenue	1,209	874
Consumable and other products
Revenue recognition
Revenue	6,145	6,131
Consumable and other products | NA
Revenue recognition
Revenue	2,924	3,619
Consumable and other products | EMEA
Revenue recognition
Revenue	2,704	2,088
Consumable and other products | Asia Pacific
Revenue recognition
Revenue	517	424
Service and other revenue
Revenue recognition
Revenue	5,762	2,790
Service and other revenue | NA
Revenue recognition
Revenue	4,646	2,394
Service and other revenue | EMEA
Revenue recognition
Revenue	521	342
Service and other revenue | Asia Pacific
Revenue recognition
Revenue	595	54
Service-type warranties
Revenue recognition
Revenue	1,179	960
Service-type warranties | NA
Revenue recognition
Revenue	748	689
Service-type warranties | EMEA
Revenue recognition
Revenue	379	234
Service-type warranties | Asia Pacific
Revenue recognition
Revenue	52	37
Research services
Revenue recognition
Revenue	4,287	1,504
Research services | NA
Revenue recognition
Revenue	3,667	1,504
Research services | EMEA
Revenue recognition
Revenue	82
Research services | Asia Pacific
Revenue recognition
Revenue	538
Other services
Revenue recognition
Revenue	296	326
Other services | NA
Revenue recognition
Revenue	231	201
Other services | EMEA
Revenue recognition
Revenue	60	108
Other services | Asia Pacific
Revenue recognition
Revenue	5	$ 17
Collaboration and license revenue
Revenue recognition
Revenue	132
Collaboration and license revenue | NA
Revenue recognition
Revenue	122
Collaboration and license revenue | EMEA
Revenue recognition
Revenue	$ 10