Income Taxes (Tables)
 12 Months Ended
Dec. 31, 2016
Income Tax Disclosure [Abstract]  
Summary of Income Tax Current and Deferred Provision

The following table presents the current and deferred provision for income taxes for the years ended December 31 (in thousands):

 

 

 

2016

 

 

2015

 

 

2014

 

Current:

 

 

 

 

 

 

 

 

 

 

 

 

Federal

 

$

—

 

 

$

—

 

 

$

—

 

State

 

 

22

 

 

 

30

 

 

 

27

 

Foreign

 

 

69

 

 

 

87

 

 

 

25

 

 

 

 

91

 

 

 

117

 

 

 

52

 

Deferred:

 

 

 

 

 

 

 

 

 

 

 

 

Federal

 

 

60

 

 

 

61

 

 

 

60

 

State

 

 

—

 

 

 

—

 

 

 

—

 

Foreign

 

 

—

 

 

 

—

 

 

 

—

 

 

 

 

60

 

 

 

61

 

 

 

60

 

 

 

$

151

 

 

$

178

 

 

$

112

 

 
Federal Income Tax Provision Compared With Statutory Rates

The provision for income taxes differs from the amount that would result from applying the federal statutory rate as follows for the years ended December 31:

 

 

 

2016

 

 

 

2015

 

 

 

2014

 

 

Statutory regular federal income tax rate

 

 

(34.0

)

%

 

 

(34.0

)

%

 

 

(34.0

)

%

Change in valuation allowance

 

 

40.4

 

%

 

 

40.2

 

%

 

 

37.4

 

%

State tax benefit (net of federal benefit)

 

 

(3.0

)

%

 

 

(3.1

)

%

 

 

(3.3

)

%

Research credits

 

 

(3.4

)

%

 

 

(3.1

)

%

 

 

(1.9

)

%

Foreign amounts with no tax benefit

 

 

0.2

 

%

 

 

0.1

 

%

 

 

(0.1

)

%

Non-deductible expenses

 

 

0.6

 

%

 

 

0.4

 

%

 

 

1.0

 

%

Effect of change in rate

 

 

0.5

 

%

 

 

0.9

 

%

 

 

2.3

 

%

Other

 

 

(0.2

)

%

 

 

(0.5

)

%

 

 

(0.8

)

%

Total

 

 

1.1

 

%

 

 

0.9

 

%

 

 

0.6

 

%

 
Summary of Net Deferred Tax Assets and Net Deferred Tax Liabilities

The components of the deferred income tax assets and liabilities as of December 31 (in thousands):

 

 

2016

 

 

2015

 

Capitalized intangible assets for tax purposes

$

47

 

 

$

104

 

Reserves not currently deductible

 

2,117

 

 

 

2,527

 

Deferred revenue

 

8

 

 

 

8

 

Stock options

 

4,966

 

 

 

4,072

 

State taxes

 

9

 

 

 

9

 

Income tax credits

 

2,379

 

 

 

2,471

 

Inventory

 

940

 

 

 

905

 

Property and equipment

 

201

 

 

 

345

 

Other comprehensive income

 

252

 

 

 

320

 

Unrealized gain on foreign currency

 

136

 

 

 

136

 

Net operating losses

 

43,687

 

 

 

38,753

 

Total deferred tax assets

 

54,742

 

 

 

49,650

 

Valuation allowance

 

(54,310

)

 

 

(49,514

)

Net deferred tax assets

 

432

 

 

 

136

 

Capitalized intangible assets

 

(876

)

 

 

(813

)

Other

 

(354

)

 

 

(61

)

Total deferred tax liabilities

 

(1,230

)

 

 

(874

)

Net deferred tax liabilities

$

(798

)

 

$

(738

)

 
Summary of Unrecognized Tax Benefits

The following table summarizes the activity related to the Company’s unrecognized tax benefits during the year ended December 31, 2016 (in thousands):

 

Balance at January 1, 2016

 

$

568

 

Additions for tax positions related to the prior year

 

 

—

 

Lapse of statute of limitations

 

 

—

 

Balance at December 31, 2016

 

$

568