Note 7 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2014

Income Tax Disclosure [Abstract]

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

	Year Ended December 31,
	2014			2013			2012
U.S.	$	(10,592	)	$	(4,919	)	$	(6,767	)
Foreign		199			118			437
Loss before income taxes	$	(10,393	)	$	(4,801	)	$	(6,330	)

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

	Year Ended December 31,
	2014			2013			2012
Current:
Federal	$	(7	)	$	(329	)	$	(13	)
State		19			7			(56	)
Foreign		110			159			366
		122			(163	)		297
Deferred:
Federal		32			33			(12	)
State		—			—			—
Foreign		65			76			(67	)
		97			109			(79	)
Tax (benefit) provision	$	219		$	(54	)	$	218

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

	December 31,
	2014			2013
Net operating loss	$	12,138		$	11,014
Stock-based compensation		3,884			3,806
Other accruals and reserves		4,735			3,686
Credits		3,808			3,121
Foreign		295			360
Accrued warranty		417			441
Depreciation and amortization		998			224
Other		66			470
Deferred tax asset before valuation allowance		26,341			23,122
Valuation allowance		(26,046	)		(22,762	)
Deferred tax asset after valuation allowance		295			360
Deferred tax liability on goodwill		(71	)		(39	)
Net deferred tax asset	$	224		$	321

Schedule of Deferred Tax Reported in Balance Sheet [Table Text Block]

	December 31,
	2014			2013
Deferred tax asset (current portion)	$	26		$	31
Deferred tax asset, net of current portion		269			329
Accrued liabilities (non-current deferred tax liability)		(71	)		(39	)
Net deferred tax asset after valuation allowance	$	224		$	321

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

	Year Ended December 31,
	2014			2013			2012
U.S. federal statutory income tax rate		34.00	%		35.00	%		35.00	%
State tax rate, net of federal benefit		1.62			1.57			3.28
Benefit for research and development credit		7.24			19.91			3.40
Foreign rate differential		(1.04	)		(4.53	)		(1.49	)
Changes in unrecognized tax benefits		(0.53	)		2.60			1.06
Foreign income inclusion		—			—			(0.05	)
Income tax refund		0.08			0.19			1.07
Stock-based compensation		(5.56	)		(34.33	)		(21.31	)
Meals and entertainment		(1.11	)		(2.10	)		(1.68	)
Tax effect of other comprehensive income		—			—			0.28
Valuation allowance		(36.58	)		(17.82	)		(21.15	)
Other		(0.22	)		0.63			(1.86	)
Effective tax rate		(2.10	)%		1.12	%		(3.45	)%

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

	Year Ended December 31,
	2014		2013			2012
Balance at beginning of year	$	535	$	536		$	583
Increases related to prior year tax positions		—		36			—
Increases related to current year tax positions		62		116			29
Decreases related to lapsing of statute of limitations		—		(153	)		(76	)
Balance at end of year	$	597	$	535		$	536