Stock-based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024
Stock-based Compensation
Weighted-average grant-date per share fair values granted (in USD per share)	$ 0.42	$ 1.45
Stock-based options forfeited (in shares)	3,037,128
Future compensation cost for awards not vested	$ 3.1
Weighted-average period compensation cost of unvested awards to be expensed (in years)	2 years 1 month 6 days
2014 Stock Incentive Plan
Stock-based Compensation
Terms (in years)	10 years
Vesting period (in years)	4 years
Shares available for issuance (in shares)	7,700,000
2014 Employee Stock Purchase Plan
Stock-based Compensation
Shares available for issuance (in shares)	200,000
Discount to the market price (as a percent)	15.00%
Cash Preservation Plan, 2025
Stock-based Compensation
Stock-based options forfeited (in shares)	3,000,000
Stock options \| 2017 Stock Incentive Plan
Stock-based Compensation
Terms (in years)	10 years
Vesting period (in years)	4 years

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Discount rate from fair value on purchase date that participants pay for shares.

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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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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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