Stockholders' Deficit (Shares Reserved for Future Issuance) (Details) - shares	Sep. 30, 2024	Dec. 31, 2023
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock options outstanding	3,934,731	3,165,216
Shares issuable under the Employee stock purchase plan	11,890
Shares available for future grants under the 2016 Plan	3,219,158
Warrants outstanding	19,365,847
Shares issuable upon the conversion of convertible debt	22,495,614
Total shares reserved	49,257,240
Restricted stock unit
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Unvested restricted stock units	230,000
Equity Incentive Plan 2016
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Shares available for future grants under the 2016 Plan	3,219,158

Number of shares issuable upon conversion of convertible debt.

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Number of warrants or rights outstanding.

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Aggregate number of common shares reserved for future issuance.

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The shares that, although not legally released, will be released by a future scheduled and committed debt service payment and will be allocated to employees for service rendered in the current accounting period. The ESOP documents typically define the period of service to which the shares relate. ESOP shares are released to compensate employees directly, to settle employer liabilities for other employee benefits, and to replace dividends on allocated shares that are used for debt service.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of options outstanding, including both vested and non-vested options.

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