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Debt - Additional Information (Details) - USD ($) | 3 Months Ended | 6 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020 | Nov. 30, 2020 | Jan. 31, 2019
Debt Instrument [Line Items] |  |  |  |  |  |  |
Long-term Debt | $ 35,000,000 |  | $ 35,000,000 |  |  |  |
IPO |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Proceeds from issuance of common stock |  |  | $ 60,000,000.0 |  |  |  |
2019 Warrants |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Warrant term | 7 years 9 months 18 days |  | 7 years 9 months 18 days |  |  |  |
Fair value of warrants |  |  | $ 200,000 |  |  |  |
Senior Secured 2019 Term Loan |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt instrument, term |  |  | 4 years |  |  |  |
Debt instrument payment terms |  |  | The 2019 Term Loan required 18 monthly interest-only payments, which began on January 31, 2019, followed by 30 equal monthly installments of principal, plus interest. The interest-only period was extended by an additional six months upon achievement of the Tranche Three Milestone. |  |  |  |
Debt instrument, frequency of periodic payment |  |  | interest-only payments |  |  |  |
Debt instrument interest payment term |  |  | 18 months |  |  |  |
Debt instrument principal and interest payment term |  |  | 30 months |  |  |  |
Debt instrument interest payment extended term |  |  | 6 months |  |  |  |
Debt instrument, effective interest rate | 14.52% |  | 14.52% |  |  |  |
Interest expense, debt | $ 0.0 | $ 500,000 | $ 0.0 | $ 1,100,000 |  |  |
Debt issuance costs | 1,500,000 |  | $ 1,500,000 |  |  |  |
Debt discount amortized term |  |  | 4 years |  |  |  |
Percentage of prepayment premium year one |  |  | 3.00% |  |  |  |
Percentage of prepayment premium year two |  |  | 2.00% |  |  |  |
Percentage of prepayment premium year three |  |  | 1.00% |  |  |  |
Percentage of final payment fee |  |  | 5.00% |  |  |  |
Debt Instrument, Covenant Description |  |  | The Company was subject to financial covenants related to minimum trailing revenue targets that began on January 1, 2019, and are tested on a monthly basis. If only Tranche One Loans were funded, the Company had to achieve minimum net revenue of $7 million over a trailing 12-month period increasing to a maximum net revenue covenant of $35 million for the trailing 12-month period ending December 31, 2022, and thereafter. If only Tranche One Loans and Tranche Two Loans had been funded, the Company had to achieve minimum net revenue of $7 million over a trailing 12-month period increasing to a maximum net revenue covenant of $37.3 million for the 12-month period ending December 31, 2022, and thereafter. If Tranche Three Loans had been funded regardless of whether Tranche Two Loans have been funded, the Company had to achieve minimum net revenue of $15 million over a trailing 12-month period increasing to a maximum net revenue covenant of $46.7 million for the 12-month period ending December 31, 2022, and thereafter. |  |  |  |
Senior Secured 2019 Term Loan | London Interbank Offered Rate (LIBOR) |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt instrument, variable rate |  |  | 6.75% |  |  |  |
Senior Secured 2019 Term Loan | Tranche One Loans |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  |  | $ 12,000,000.0
Debt instrument covenant minimum revenue | 7,000,000 |  | $ 7,000,000 |  |  |  |
Debt instrument covenant maximum revenue | 35,000,000 |  | 35,000,000 |  |  |  |
Senior Secured 2019 Term Loan | Tranche Two Loans |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  |  | 2,000,000.0
Senior Secured 2019 Term Loan | Tranche Three Loans |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  |  | 6,000,000.0
Debt instrument covenant minimum revenue | 15,000,000 |  | 15,000,000 |  |  |  |
Debt instrument covenant maximum revenue | $ 46,700,000 |  | $ 46,700,000 |  |  |  |
Senior Secured 2019 Term Loan | Tranche Three Loans | Series C Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Warrants issued to purchase shares of convertible preferred stock | 12,649 |  | 12,649 |  |  |  |
Senior Secured 2019 Term Loan | Tranche One and Two Loans |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Long-term Debt | $ 14,000,000.0 |  | $ 14,000,000.0 |  |  |  |
Debt instrument covenant minimum revenue | 7,000,000 |  | 7,000,000 |  |  |  |
Debt instrument covenant maximum revenue | $ 37,300,000 |  | $ 37,300,000 |  |  |  |
Senior Secured 2019 Term Loan | Tranche One and Two Loans | Series C Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Warrants issued to purchase shares of convertible preferred stock | 29,514 |  | 29,514 |  |  |  |
Warrant term | 10 years |  | 10 years |  |  |  |
Class of warrant exercise price | $ 9.49 |  | $ 9.49 |  |  |  |
Senior Secured 2020 Term Loan |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt instrument, term |  |  | 5 years |  |  |  |
Debt instrument payment terms |  |  | The 2020 Term Loan requires 24 monthly interest-only payments, which began on December 1, 2020, followed by 36 equal monthly installments of principal, plus interest. |  |  |  |
Debt instrument interest payment term |  |  | 24 months |  |  |  |
Debt instrument principal and interest payment term |  |  | 36 months |  |  |  |
Debt instrument interest payment extended term |  |  | 12 months |  |  |  |
Debt instrument, effective interest rate | 13.59% |  | 13.59% |  |  |  |
Interest expense, debt | $ 1,100,000 | $ 0.0 | $ 2,200,000 | $ 0.0 |  |  |
Debt issuance costs | 500,000 |  | $ 500,000 |  |  |  |
Debt discount amortized term |  |  | 5 years |  |  |  |
Percentage of prepayment premium year one |  |  | 3.00% |  |  |  |
Percentage of prepayment premium year two |  |  | 2.00% |  |  |  |
Percentage of prepayment premium year three |  |  | 1.00% |  |  |  |
Percentage of final payment fee |  |  | 6.00% |  |  |  |
Accrued amount related accretion on maturity payments | $ 700,000 |  | $ 700,000 |  | $ 500,000 |  |
Senior Secured 2020 Term Loan | Series F Redeemable Convertible Preferred Stock |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Warrants issued to purchase shares of convertible preferred stock | 300,000 |  | 300,000 |  |  |  |
Warrant term | 10 years |  | 10 years |  |  |  |
Class of warrant exercise price | $ 21.88 |  | $ 21.88 |  |  |  |
Fair value of warrants |  |  | $ 1,800,000 |  |  |  |
Senior Secured 2020 Term Loan | London Interbank Offered Rate (LIBOR) |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt instrument, variable rate |  |  | 7.00% |  |  |  |
Senior Secured 2020 Term Loan | Tranche One Loans |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  | $ 12,000,000.0 |
Senior Secured 2020 Term Loan | Tranche Two Loans |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  | 2,000,000.0 |
Senior Secured 2020 Term Loan | Tranche Three Loans |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  | 21,000,000.0 |
Long-term Debt |  |  |  |  |  | 21,000,000.0 |
Revolving 2020 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Line of credit facility, commitment fee description |  |  | An unused line fee of 0.5% is payable monthly based on the average unused balance and a collateral management fee of 0.5% is payable monthly based on the outstanding balance of the 2020 Revolver. |  |  |  |
Line of credit facility, unused capacity, commitment fee percentage |  |  | 0.50% |  |  |  |
Line of credit facility collateral fees | 0.50% |  | 0.50% |  |  |  |
Line of credit facility commitment fee amount |  |  | $ 15,000,000.0 |  |  |  |
Line of credit facility, current borrowing capacity | $ 5,000,000.0 |  | $ 5,000,000.0 |  |  |  |
Revolving 2020 | London Interbank Offered Rate (LIBOR) |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Debt instrument, variable rate |  |  | 4.50% |  |  |  |
Mid Cap Financial Services |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  | 40,000,000.0 | 25,000,000.0
Mid Cap Financial Services | Senior Secured 2019 Term Loan |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  |  | 20,000,000.0
Mid Cap Financial Services | Senior Secured 2020 Term Loan |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  | 35,000,000.0 |
Mid Cap Financial Services | Revolver 2019 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  |  | $ 5,000,000.0
Mid Cap Financial Services | Revolving 2020 |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |
Maximum borrowing capacity |  |  |  |  |  | $ 5,000,000.0 |

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