Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Assets
Cash and cash equivalents	$ 166,485	$ 181,270
Accounts receivable, net	13,241	13,669
Other receivables	4,679	4,660
Inventory, net	10,854	11,096
Prepaid expenses and other assets	5,457	5,186
Total current assets	200,716	215,881
Restricted cash, non-current	100	100
Property and equipment, net	7,314	7,095
Operating lease right-of-use assets	6,824	7,443
Goodwill	2,483	2,483
Other intangible assets, net	75	87
Deferred tax asset	1,570	2,163
Total assets	219,082	235,252
Liabilities and shareholders' equity
Accounts payable	4,461	2,420
Accrued liabilities	8,490	10,396
Current portion of operating lease liability	1,038	984
Deferred income	43	19
Total current liabilities	14,032	13,819
Long-term portion of operating lease liability	7,010	7,710
Long-term portion of loans payable	32	32
Total liabilities	21,074	21,561
Commitments and contingencies (Note 12)
Shareholders' equity:
Ordinary shares, £0.006705 nominal value; 39,293,813 and 39,824,703 shares authorized at March 31, 2020 and December 31, 2019, respectively, and 25,945,744 and 26,419,961 shares issued and outstanding at March 31, 2020 and December 31, 2019, respectively	272	276
Additional paid-in capital	299,574	304,909
Accumulated deficit	(91,650)	(84,033)
Accumulated other comprehensive loss	(10,188)	(7,461)
Total shareholders' equity	198,008	213,691
Total liabilities and shareholders' equity	$ 219,082	$ 235,252