Financial Instruments (Tables)

6 Months Ended

Jun. 30, 2018

Financial Instruments

Summary of assets measured at fair value on a recurring basis

Below is a summary of assets measured at fair value on a recurring basis (in thousands):

	As of June 30, 2018
	Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Assets:
Cash and cash equivalents:
Money market funds	$	41,657	$	—	$	—	$	41,657
U.S. reverse repurchase agreements	—		3,000		—		3,000
Total assets	$	41,657	$	3,000	$	—	$	44,657

	As of December 31, 2017
	Quoted Prices in Active Markets (Level 1)		Significant Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Assets:
Cash and cash equivalents:
Money market funds	$	13,588	$	—	$	—	$	13,588
Total assets	$	13,588	$	—	$	—	$	13,588