Fair Value Measurements (Tables)

3 Months Ended

Oct. 28, 2017

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Schedule of Financial Instruments Measured at Fair Value on Recurring Basis Based on Fair Value Hierarchy

The following table sets forth our financial instruments that were measured at fair value on a recurring basis based on the fair value hierarchy (in thousands):

	October 28, 2017
	Level 1		Level 2		Level 3		Total
Financial Liabilities:
Preferred stock warrant liability	$	—	$	—	$	17,608	$	17,608
Total	$	—	$	—	$	17,608	$	17,608

	July 29, 2017
	Level 1		Level 2		Level 3		Total
Financial Liabilities:
Preferred stock warrant liability	$	—	$	—	$	26,679	$	26,679
Total	$	—	$	—	$	26,679	$	26,679

Schedule of Key Assumptions Used for Valuation of Preferred Stock Warrant Liability

The key assumptions used in the Black-Scholes option-pricing model for the valuation of the preferred stock warrant liability upon remeasurement were as follows:

	Three Months Ended
	October 28, 2017			October 29, 2016
Expected term (in years)		2.0			5.3
Fair value of underlying shares	$	16.53		$	8.89
Volatility		39.2	%		40.2	%
Risk free interest rate		1.6	%		1.4	%
Dividend yield		—	%		—	%

Schedule of Changes in Fair Value of Preferred Stock Warrant Liability

The following table sets forth a summary of the changes in the fair value of the preferred stock warrant liability (in thousands):

	Three Months Ended
	October 28, 2017
Balance at July 29, 2017	$	26,679
Change in fair value		(9,071	)
Ending Balance at October 28, 2017	$	17,608