Fair Value Measurement and Financial Instruments - Summary of Fair Value Inputs and Assumptions (Details)	Jul. 02, 2018 $ / shares
Estimated Fair Value of Convertible Preferred Stock | Series E
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value assumption	$ 26.41
Estimated Fair Value of Convertible Preferred Stock | Series F
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value assumption	26.41
Exercise Price | Series E
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Exercise price	19.55
Exercise Price | Series F
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Exercise price	$ 9.73
Remaining Term (in years) | Series E
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Remaining term (in years)	4 years 6 months
Remaining Term (in years) | Series F | Minimum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Remaining term (in years)	2 years 7 months 6 days
Remaining Term (in years) | Series F | Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Remaining term (in years)	6 years 6 months
Risk-free Interest Rate | Series E
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Risk-free interest rate	2.7
Risk-free Interest Rate | Series F | Minimum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Risk-free interest rate	2.6
Risk-free Interest Rate | Series F | Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Risk-free interest rate	2.8
Expected Volatility | Series E
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Risk-free interest rate	43
Expected Volatility | Series F
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Risk-free interest rate	43
Measurement Input, Expected Dividend Rate | Series E
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Risk-free interest rate	0
Measurement Input, Expected Dividend Rate | Series F
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Risk-free interest rate	0