Fair value measurements (Tables)

12 Months Ended

Dec. 31, 2019

Fair Value Disclosures [Abstract]

Fair Value of Financial Assets

The following table presents the Company’s assets that are measured at fair value on a recurring basis (in thousands): 

	December 31, 2019								December 31, 2018
	Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3		Total
Cash equivalents and short-term investments:
Money market funds	$	7,638	$	—	$	—	$	7,638	$	7,481	$	—	$	—	$	7,481
Total	$	7,638	$	—	$	—	$	7,638	$	7,481	$	—	$	—	$	7,481
Mutual funds held in Rabbi Trust, recorded in other long-term assets	$	616	$	—	$	—	$	616	$	465	$	—	$	—	$	465

Fair Value of Financial Liabilities

The following table presents the Company’s liabilities that are measured at fair value on a recurring basis (in thousands): 

	As of December 31, 2018
	Level 1		Level 2		Level 3		Total
Rusnano payment derivative	$	—	$	—	$	2,000	$	2,000
Total	$	—	$	—	$	2,000	$	2,000