Note 17 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Notes Tables

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

	Year Ended December 31,
	2020		2019		2018
Current:
Federal	$	—	$	—	$	—
State		3		2		3
Foreign		235		488		106
Total Current		238		490		109
Deferred:
Federal		—		—		—
State		—		—		—
Foreign		—		—		—
Total Deferred		—		—		—
Provision for income taxes	$	238	$	490	$	109

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

	December 31, 2020			December 31, 2019			December 31, 2018
Deferred tax assets:
Net operating loss carry-forwards	$	14,161		$	6,924		$	43,822
Research and development tax credits		2,497			1,591			3,357
Capitalized research and development		4,534			4,773			2,326
Sale of future royalties		7,178			7,486			8,383
Lease Liability		1,695			492			—
Accruals, reserves and other		1,327			1,253			714
Total deferred tax assets		31,392			22,519			58,602
Valuation allowance		(21,952	)		(13,365	)		(48,626	)
Deferred tax assets net of valuation allowance		9,440			9,154			9,976
Deferred tax liabilities:
Intangible assets		(7,832	)		(8,730	)		(9,976	)
Right-of-use assets		(1,608	)		(424	)		—
Total deferred tax liabilities		(9,440	)		(9,154	)		(9,976	)
Net deferred tax assets	$	—		$	—		$	—

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

	Year Ended December 31,
	2020			2019			2018
U.S. federal taxes at statutory rate		21.0	%		21.0	%		21.0	%
State taxes (net of federal benefit)		2.9			0.4			0.6
Foreign rate differential		(0.7	)		(2.6	)		3.1
Global intangible low-taxed income		—			—			(8.8	)
Permanently non-deductible items		2.2			(3.7	)		(2.5	)
Tax credits		2.8			1.7			2.1
Change in valuation allowance		(26.8	)		194.2			(20.4	)
Tax attributes write-off due to change in control		0.5			(208.3	)		—
Prior year true-up		(2.5	)		(0.9	)		—
NOL and credit adjustments		—			—			(3.8	)
Bargain purchase gain		—			—			8.1
Other		(0.1	)		(4.5	)		—
Provision for income taxes		(0.7	)%		(2.7	)%		(0.6	)%

Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block]

	Year Ended December 31,
	2020			2019			2018
Beginning Balance	$	851		$	1,582		$	1,404
Additions based on tax positions related to the current year		431			159			181
Decreases related to prior years' tax positions		(1	)		(890	)		(3	)
Ending Balance	$	1,281		$	851		$	1,582