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v3.24.1

Outstanding Debt (Details) |  |  |  |  | 1 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 20, 2023 USD ($) | Sep. 10, 2023 USD ($) shares | Jan. 26, 2023 USD ($) $ / shares shares | Feb. 28, 2022 USD ($) $ / shares shares | Nov. 30, 2022 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Jan. 27, 2023 shares | Jan. 12, 2023 $ / shares | Sep. 15, 2020 USD ($) debt investor
Short-term Debt [Line Items] |  |  |  |  |  |  |  |  |  |
Periodic payment |  |  |  | $ 2,600,000 |  |  |  |  |  |
Escrow amount |  |  |  |  |  | $ 540,000 |  |  |  |
Exercise price (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  | $ 10.00 |
Warrant fair value |  |  |  |  |  |  | $ 0 |  |  |
Expected stock price volatility |  |  |  |  |  | 80.00% | 79.00% |  |  |
Risk-free rate of interest |  |  |  |  |  | 3.70% | 2.50% |  |  |
Warrants outstanding, term (in years) |  |  |  |  |  | 1 year |  | 5 years |  |
Conversion price (in dollars per share) | $ / shares |  |  |  | $ 5.75 |  |  |  |  |  |
Cash |  |  |  | $ 1,400,000 |  |  |  |  |  |
Remaining principal amount |  |  |  | 1,400,000 |  |  |  |  |  |
Interest payable |  |  |  | 41,000 |  |  |  |  |  |
Debt conversion, principal amount |  |  |  | 1,200,000 |  |  |  |  |  |
2023 Notes Warrants |  |  |  |  |  |  |  |  |  |
Short-term Debt [Line Items] |  |  |  |  |  |  |  |  |  |
Warrants (in shares) | shares |  |  | 76,000 |  |  |  |  | 76,000 |  |
Exercise price (in dollars per share) | $ / shares |  |  | $ 9.00 |  |  |  |  |  |  |
Weighted average remaining contractual life, options vested and exercisable (in years) |  |  | 5 years |  |  |  |  |  |  |
Expected stock price volatility |  |  | 81.50% |  |  |  |  |  |  |
Risk-free rate of interest |  |  | 3.62% |  |  |  |  |  |  |
Warrants outstanding, term (in years) |  |  | 5 years |  |  |  |  |  |  |
Warrant, fair value |  |  | $ 400,000 |  |  |  |  |  |  |
2023 Notes Warrants | Black-Scholes Option Pricing Model |  |  |  |  |  |  |  |  |  |
Short-term Debt [Line Items] |  |  |  |  |  |  |  |  |  |
Warrant fair value |  |  | 400,000 |  |  |  |  |  |  |
Unsecured Debt |  |  |  |  |  |  |  |  |  |
Short-term Debt [Line Items] |  |  |  |  |  |  |  |  |  |
Aggregate principal amount |  |  |  | $ 600,000 |  |  |  |  |  |
Common stock issued (in shares) | shares |  |  |  | 200,000 |  |  |  |  |  |
Conversion price (in dollars per share) | $ / shares |  |  |  | $ 3.00 |  |  |  |  |  |
Debt conversion, amount |  | $ 2,400,000 |  |  |  |  |  |  |  |
Debt conversion, common stock (in shares) | shares |  | 800,000 |  |  |  |  |  |  |  |
Unsecured Debt | Letter Agreement |  |  |  |  |  |  |  |  |  |
Short-term Debt [Line Items] |  |  |  |  |  |  |  |  |  |
Aggregate principal amount |  |  |  | $ 2,000,000 |  |  |  |  |  |
2023 Secured Mortgage Loan | Secured Debt |  |  |  |  |  |  |  |  |  |
Short-term Debt [Line Items] |  |  |  |  |  |  |  |  |  |
Aggregate principal amount | $ 3,300,000 |  |  |  |  |  |  |  |  |
Interest rate (as a percent) | 8.25% |  |  |  |  |  |  |  |  |
Periodic payment | $ 25,000 |  |  |  |  |  |  |  |  |
Debt issuance costs | $ 341,000 |  |  |  |  |  |  |  |  |
Escrow amount |  |  |  |  |  | $ 540,000 |  |  |  |
2023 Note | Unsecured Debt |  |  |  |  |  |  |  |  |  |
Short-term Debt [Line Items] |  |  |  |  |  |  |  |  |  |
Aggregate principal amount |  |  | $ 7,600,000 |  |  |  |  |  |  |
Interest rate (as a percent) |  |  | 10.00% |  |  |  |  |  |  |
2023 Note | Unsecured Debt | 2023 Notes Warrants |  |  |  |  |  |  |  |  |  |
Short-term Debt [Line Items] |  |  |  |  |  |  |  |  |  |
Aggregate principal amount |  |  |  |  |  | 7,300,000 |  |  |  |
Debt discount |  |  |  |  |  | 300,000 |  |  |  |
September 2020 Notes | Unsecured Debt |  |  |  |  |  |  |  |  |  |
Short-term Debt [Line Items] |  |  |  |  |  |  |  |  |  |
Aggregate principal amount |  |  |  |  |  |  |  |  |  | $ 10,000,000
Number of debt instruments | debt |  |  |  |  |  |  |  |  |  | 2
Number of investors | investor |  |  |  |  |  |  |  |  |  | 2
Repayments of long-term debt |  |  |  |  | $ 5,600,000 |  |  |  |  |
Interest expense |  |  |  |  |  | $ 800,000 | $ 800,000 |  |  |

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- Definition Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480429/718-10-50-2 + Details
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