Equity Incentive and Other Plans - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended
Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2024
2021 Plan
Number of Shares
Outstanding (in shares)			4,976
Exercised (in shares)			0
Forfeited or expired (in shares)			0
Outstanding (in shares)	4,976	4,976	4,976
Vested and exercisable (in shares)	2,593		2,593
Weighted Average Exercise Price
Outstanding (in usd per share)			$ 39.6
Exercised (in usd per share)			0
Forfeited or expired (in usd per share)			0
Outstanding (in usd per share)	$ 39.6	$ 39.6	39.6
Vested and exercisable (in usd per share)	$ 39.6		$ 39.6
Aggregate Intrinsic Value
Outstanding	$ 0	$ 0	$ 0
Vested and exercisable	$ 0		$ 0
Weighted Average Remaining Contractual Term (in years)
Outstanding	8 years 4 months 20 days	8 years 7 months 20 days
Vested and exercisable	8 years 4 months 20 days
2018 Plan
Number of Shares
Outstanding (in shares)			116,451
Forfeited or expired (in shares)			(201)
Outstanding (in shares)	116,250	116,451	116,250
Vested and exercisable (in shares)	69,498		69,498
Weighted Average Exercise Price
Outstanding (in usd per share)			$ 34.24
Forfeited or expired (in usd per share)			135.21
Outstanding (in usd per share)	$ 34.06	$ 34.24	34.06
Vested and exercisable (in usd per share)	$ 27.89		$ 27.89
Aggregate Intrinsic Value
Outstanding	$ 0	$ 3	$ 0
Vested and exercisable	$ 0		$ 0
Weighted Average Remaining Contractual Term (in years)
Outstanding	4 years 4 months 6 days	4 years 7 months 24 days
Vested and exercisable	5 years 6 months 14 days

Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Intrinsic Value

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Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Weighted Average Remaining Contractual Term

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

For presentations that combine terminations, 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 or that expired.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Weighted average price of options that were either forfeited or expired.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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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.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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