Note 12 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Notes Tables

Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]

(in thousands)	201 6			201 5			201 4
Domestic (United Kingdom)	$	(730	)	$	1,400		$	(158	)
Foreign (United States)		(25,393	)		(25,732	)		(21,862	)
Loss before income taxes	$	(26,123	)	$	(24,332	)	$	(22,020	)

Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]

(in thousands)	201 6			201 5			20 14
Current:
Federal	$	—		$	—		$	—
U.K.		—			—			—
Japan		(85	)		(116	)		(119	)
China		(12	)		—			—
State		(51	)		(30	)		(35	)
Total current provision		(148	)		(146	)		(154	)
Deferred:
Federal		752			—			—
U.K.		2,630			—			—
State		540			—			—
Total deferred benefit		3,922			—			—
Income tax benefit (expense)		3,774			(146	)		(154	)

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	201 6			201 5			201 4
Income tax rate	20.0		%	20.3		%		21.5	%
U.K. research and development credit		1.8			1.3			1.7
Other		(2.1	)		(1.1	)		(1.2	)
Effect of foreign tax rate differential		16.8			10.7			17.9
Valuation allowance		(22.1	)		(31.7	)		(40.6	)
Effective income tax rate		14.4	%		(0.5	)%		(0.7	)%

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

(in thousands)	201 6			201 5
Deferred tax assets:
Long term deferred tax assets:
U.S. federal net operating losses	$	42,165		$	32,095
State net operating loss (net of federal)		5,198			4,021
U.S. federal research and development credit		273			155
U.K. net operating loss		2,419			5,217
Share options		1,884			1,251
Accrued liabilities		526			177
State credits		85			—
Other		—			160
Total deferred tax assets		52,550			43,076
Valuation allowance		(46,473	)		(43,076	)
Total deferred tax assets	$	6,077		$	—
Deferred tax liabilities:
Long term deferred tax liabilities:
Other assets	$	(29	)	$	—
Intangible assets		(3,418	)		—
Total deferred tax liabilities	$	(3,447	)	$	—

Summary of Valuation Allowance [Table Text Block]

(in thousands)	201 6		201 5		201 4
Beginning of year (January 1)	$	43,076	$	35,361	$	26,413
Increase in valuation allowance		3,397		7,715		8,948
End of year (December 31)	$	46,473	$	43,076	$	35,361