Balance sheet components (Tables)
12 Months Ended
Dec. 31, 2015
Balance sheet components  
Schedule cash, cash equivalents, short-term investments, and long-term investments

        The following is a summary of cash equivalents and marketable securities (in thousands).

                                                                                                                                                                                    

 

 

December 31, 2015

 

 

 

Amortized
Cost

 

Gross
Unrealized
Gains

 

Gross
Unrealized
Losses

 

Estimated
Fair Value

 

Money market funds

 

$

39,998

 

$

 

$

 

$

39,998

 

U.S. treasury notes

 

 

4,006

 

 

 

 

 

 

4,006

 

U.S. government agency securities

 

 

65,586

 

 

1

 

 

(16

)

 

65,571

 

​  

​  

​  

​  

​  

​  

​  

​  

 

 

$

109,590

 

$

1

 

$

(16

)

$

109,575

 

​  

​  

​  

​  

​  

​  

​  

​  

​  

​  

​  

​  

​  

​  

​  

​  

Reported as:

 

 

 

 

 

 

 

 

 

 

 

 

 

Cash equivalents

 

 

 

 

 

 

 

 

 

 

$

50,964

 

Restricted cash

 

 

 

 

 

 

 

 

 

 

 

4,831

 

Marketable securities

 

 

 

 

 

 

 

 

 

 

 

53,780

 

​  

​  

Total cash equivalents, restricted cash and marketable securities

 

 

 

 

 

 

 

 

 

 

$

109,575

 

​  

​  

​  

​  

 

                                                                                                                                                                                    

 

 

December 31, 2014

 

 

 

Amortized
Cost

 

Gross
Unrealized
Gains

 

Gross
Unrealized
Losses

 

Estimated
Fair Value

 

Money market funds

 

$

15,167 

 

$

 

$

 

$

15,167 

 

​  

​  

​  

​  

​  

​  

​  

​  

 

 

$

15,167 

 

$

 

$

 

$

15,167 

 

​  

​  

​  

​  

​  

​  

​  

​  

​  

​  

​  

​  

​  

​  

​  

​  

Reported as:

 

 

 

 

 

 

 

 

 

 

 

 

 

Cash equivalents

 

 

 

 

 

 

 

 

 

 

$

15,017 

 

Restricted cash

 

 

 

 

 

 

 

 

 

 

 

150 

 

​  

​  

Total cash equivalents, and restricted cash

 

 

 

 

 

 

 

 

 

 

$

15,167 

 

​  

​  

​  

​  

 

Schedule of available for sale securities continuous unrealized loss position

        The following table summarizes the available-for-sale securities that were in an unrealized loss position as of December 31, 2015, having been in such a position for less than 12 months, and none having been deemed to be other-than-temporarily impaired (in thousands):

                                                                                                                                                                                    

 

 

Gross
Unrealized
Losses

 

Estimated
Fair Value

 

U.S. government agency securities

 

$

16 

 

$

42,034 

 

 

Schedule of Property and equipment

        Property and equipment consisted of the following (in thousands):

                                                                                                                                                                                    

 

 

December 31,

 

 

 

2015

 

2014

 

Leasehold improvements

 

$

2,548

 

$

1,914

 

Laboratory equipment

 

 

10,461

 

 

6,528

 

Equipment under capital lease

 

 

8,224

 

 

3,735

 

Computer equipment

 

 

2,397

 

 

1,156

 

Software

 

 

2,368

 

 

831

 

Furniture and fixtures

 

 

210

 

 

158

 

Automobiles

 

 

20

 

 

 

Construction-in-progress

 

 

1,202

 

 

4,853

 

​  

​  

​  

​  

Total property and equipment, gross

 

 

27,430

 

 

19,175

 

Accumulated depreciation and amortization

 

 

(8,721

)

 

(3,503

)

​  

​  

​  

​  

Total property and equipment, net

 

$

18,709

 

$

15,672

 

​  

​  

​  

​  

​  

​  

​  

​  

 

Schedule of Accrued liabilities

        Accrued liabilities consisted of the following (in thousands):

                                                                                                                                                                                    

 

 

Year ended
December 31,

 

 

 

2015

 

2014

 

Accrued compensation and related expenses

 

$

2,307 

 

$

1,439 

 

Accrued laboratory materials purchases

 

 

426 

 

 

 

Accrued professional services

 

 

272 

 

 

1,030 

 

Accrued costs for construction-in-progress

 

 

 

 

32 

 

Other

 

 

1,248 

 

 

736 

 

​  

​  

​  

​  

Total accrued liabilities

 

$

4,253 

 

$

3,237 

 

​  

​  

​  

​  

​  

​  

​  

​