Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2017

Fair Value Disclosures [Abstract]

Assets and Liabilities Measured at Fair Value on Recurring Basis

Assets measured at fair value on a recurring basis as of September 30, 2017 and December 31, 2016 are summarized below (in thousands):

	September 30, 2017
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Direct or Indirect Observable Inputs (Level 2)		Total
Assets
Cash equivalents:
Money market funds	$	447	$	—	$	447
Corporate commercial paper		—		2,999		2,999
Corporate debt securities		—		3,752		3,752
Total cash equivalents		447		6,751		7,198
Short-term investments:
Corporate commercial paper		—		7,174		7,174
Corporate debt securities		—		6,453		6,453
Total short-term investments		—		13,627		13,627
Total assets measured at fair value	$	447	$	20,378	$	20,825

	December 31, 2016
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Direct or Indirect Observable Inputs (Level 2)		Total
Assets
Cash equivalents:
Money market funds	$	2,796	$	—	$	2,796
Corporate commercial paper		—		500		500
Total cash equivalents		2,796		500		3,296
Short-term investments:
Corporate commercial paper		—		11,465		11,465
Corporate debt securities		—		7,423		7,423
Total short-term investments		—		18,888		18,888
Total assets measured at fair value	$	2,796	$	19,388	$	22,184