Leases - Lease cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Lease, Cost [Abstract]
Lease, Cost, Total	$ 2,565
Selling, general and administrative expenses
Lease, Cost [Abstract]
Operating lease cost	1,926
Rent expenses ASC840		$ 1,000
Research and development
Lease, Cost [Abstract]
Operating lease cost	139
Rent expenses ASC840		200
Cost of goods sold
Lease, Cost [Abstract]
Operating lease cost	366
Amortization of leased assets	130
Rent expenses ASC840		$ 300
Interest Expense [Member]
Lease, Cost [Abstract]
Interest on lease liabilities	$ 4