Subsequent Events - Additional Information (Details) - SVB and WestRiver - Tranche 3 - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	9 Months Ended
Oct. 31, 2019	Sep. 30, 2019
Subsequent Event [Line Items]
Line of credit, payment terms		the interest-only period of the 2019 Loan was extended to June 30, 2020, followed by an amortization period of 33 months of equal monthly payments of principal plus interest until paid in full.
Subsequent Event
Subsequent Event [Line Items]
Proceeds from lines of credit	$ 5.0
Number of warrants issued	24,262
Exercise price of warrant	$ 3.88

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

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-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
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-Publisher FASB
-Name Accounting Standards Codification
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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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-Publisher FASB
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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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