Lease (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Finance lease cost components:
Amortization of finance lease assets	$ 20	$ 17	$ 37	$ 34
Interest on finance lease liabilities	10	14	21	30
Total finance lease costs	30	31	58	64
Operating lease cost components:
Operating lease cost	145	123	285	246
Variable lease cost	56	27	83	54
Short-term lease cost	10	30	12	52
Total operating lease costs	211	180	380	352
Total lease cost	$ 241	$ 211	$ 438	$ 416