Debt and lease liabilities (Operating Lease Liabilities) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Lessee, Lease, Description [Line Items]
Discount rate	5.50%		5.50%
Weighted average lease term	3 years 4 months 28 days		3 years 4 months 28 days
Operating rental expenses	$ 191	$ 100	$ 575	$ 278
Monthly Rental Payments | Related Party
Lessee, Lease, Description [Line Items]
Rental payments			20
Total rental payments	$ 58	$ 61	$ 180	$ 182