Subsequent Events (Details) - Subsequent Events $ / shares in Units, $ in Thousands	Oct. 01, 2019 USD ($) $ / shares shares
SVB Warrant
Subsequent Event [Line Items]
Number of securities called by warrants (in shares)	72,394
Exercise price (in dollars per share) \| $ / shares	$ 0.01
Warrants, term	10 years
Term Loan Facility \| SVB Loan Agreement
Subsequent Event [Line Items]
Term loan facility \| $	$ 5,200
Derivative, average basis spread on variable rate	7.00%
Term Loan Facility \| SVB Loan Agreement \| Prime Rate
Subsequent Event [Line Items]
Loan accrued interest rate equal to prime rate (basis points)	200.00%
Stock Options \| Non-Employee
Subsequent Event [Line Items]
Shares available for issuance (in shares)	100,000
Exercise price per share \| $ / shares	$ 4.92
Series D Preferred Stock
Subsequent Event [Line Items]
Stock issued for conversion of convertible preferred stock, shares (in shares)	1,680,000
Preferred stock, dividend percentage rate, per annum	6.00%
Series D Preferred Stock \| Restricted Stock
Subsequent Event [Line Items]
Issuance of stock on vested restricted stock units (in shares)	50,000
Restricted shares vesting term	2 years
Series D Preferred Stock \| Restricted Stock \| Cliff Vesting Date
Subsequent Event [Line Items]
Restricted shares vesting percentage	25.00%
Series D Preferred Stock \| Restricted Stock \| Ratable Monthly Installments Thereafter
Subsequent Event [Line Items]
Restricted shares vesting percentage	75.00%
Series E Financing \| Series E Financing
Subsequent Event [Line Items]
Sale of stock, number of shares issued (in shares)	88,070
Sale of stock, price per share \| $ / shares	$ 28.50
Gross proceeds from issuance of stock \| $	$ 2,510
Conversion price, per share (in dollars per share) \| $ / shares	$ 2.85
Convertible preferred stock, shares issued upon conversion (in shares)	880,700
Purchase of additional shares \| $	$ 1,250
Series E Financing \| Series E Financing \| Maximum
Subsequent Event [Line Items]
Sale of stock, number of shares issued (in shares)	131,579

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Sale Of Stock, Consideration Received On Transaction, Commitment

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Exercise price per share or per unit of warrants or rights outstanding.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Per share weighted-average price paid for shares purchased on open market for issuance under share-based payment arrangement.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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