Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2016

Fair Value Disclosures [Abstract]

Assets and Liabilities Measured at Fair Value on Recurring Basis

Assets and liabilities measured at fair value on a recurring basis are summarized below (in thousands):

	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
Corporate debt		—		—	$	—
Total cash equivalents		2,796		500		3,296
Short-term investments:
Corporate commercial paper		—		11,465		11,465
Treasury bonds		—		—		—
Corporate debt		—		7,423		7,423
Total short-term investments		—		18,888		18,888
Total assets measured at fair value	$	2,796	$	19,388	$	22,184
	December 31, 2015
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Direct or Indirect Observable Inputs (Level 2)		Total
Assets
Cash equivalents:
Money market funds	$	5,404	$	—	$	5,404
Corporate commercial paper		—		1,500		1,500
Corporate debt		—		2,269	$	2,269
Total cash equivalents		5,404		3,769		9,173
Short-term investments:
Corporate commercial paper		—		6,245		6,245
Treasury bonds		—		1,007		1,007
Corporate debt		—		6,028		6,028
Total short-term investments		—		13,280		13,280
Restricted cash equivalents—money market fund		250		—		250
Total assets measured at fair value	$	5,654	$	17,049	$	22,703