Fair Value Measurement (Tables)

12 Months Ended

Dec. 31, 2018

Fair Value Disclosures [Abstract]

Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis

The following table sets forth the fair value of the Company’s financial assets and liabilities measured at fair value on a recurring basis based on the three-tier fair value hierarchy (in thousands):

	December 31, 2018
	Level 1		Level 2		Level 3		Total
Assets
Money market funds[1]	$	15,223	$	—	$	—	$	15,223
U.S. treasury securities	66,489		—		—		66,489
Corporate bonds	—		19,720		—		19,720
Commercial paper	—		18,529		—		18,529
Liabilities
Redeemable convertible preferred stock warrants	$	—	$	—	$	—	$	—
	December 31, 2017
	Level 1		Level 2		Level 3		Total
Assets
Money market funds[1]	$	22,115	$	—	$	—	$	22,115
Liabilities
Redeemable convertible preferred stock warrants	$	—	$	—	$	422	$	422

[1] Included in cash and cash equivalents on the consolidated balance sheet

Summary of Changes in Fair Value of the Redeemable Convertible Preferred Stock Warrants

The following table sets forth a summary of the changes in the fair value of the redeemable convertible preferred stock warrants, the Company’s Level 3 financial liability, which is measured on a recurring basis (in thousands):

Balances at December 31, 2017	$	422
Change in fair value recorded in other (income) expense, net	826
Conversion of preferred stock warrants to common stock warrants	(1,248		)
Balances at December 31, 2018	$	—