Stock-based Compensation - Stock Plan Activities (Details) - $ / shares shares in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Options Outstanding
Options outstanding, stock option awards exercised (in shares)	(801)	(1,108)
Incentive Plan
Awards Available
Awards available, beginning balance (in shares)	4,206
Awards available, restricted stock awards granted (in shares)	(146)
Awards available, restricted stock awards cancelled (in shares)	313
Awards available, stock option awards granted (in shares)	(215)
Awards available, stock option awards cancelled (in shares)	437
Awards available, ending balance (in shares)	4,595
Options Outstanding
Options outstanding, beginning balance (in shares)	31,179
Options outstanding, stock option awards granted ( in shares)	215
Options outstanding, stock option awards exercised (in shares)	(529)
Options outstanding, stock option awards cancelled (in shares)	(437)
Options outstanding, ending balance (in shares)	30,428
Weighted Average Exercise Price
Weighted average exercise price, beginning balance (in usd per share)	$ 8.56
Weighted average exercise price of stock option awards granted (in usd per share)	10.55
Weighted average exercise price of stock option awards exercised (in usd per share)	5.52
Weighted average exercise price of stock option awards cancelled (in usd per share)	10.32
Weighted average exercise price, ending balance (in usd per share)	$ 8.60
Inducement Plan
Awards Available
Awards available, beginning balance (in shares)	947
Awards available, restricted stock awards granted (in shares)	(193)
Awards available, restricted stock awards cancelled (in shares)	21
Awards available, stock option awards granted (in shares)	(522)
Awards available, stock option awards cancelled (in shares)	260
Awards available, ending balance (in shares)	513
Options Outstanding
Options outstanding, beginning balance (in shares)	5,341
Options outstanding, stock option awards granted ( in shares)	522
Options outstanding, stock option awards exercised (in shares)	(173)
Options outstanding, stock option awards cancelled (in shares)	(260)
Options outstanding, ending balance (in shares)	5,430
Weighted Average Exercise Price
Weighted average exercise price, beginning balance (in usd per share)	$ 8.80
Weighted average exercise price of stock option awards granted (in usd per share)	9.66
Weighted average exercise price of stock option awards exercised (in usd per share)	3.36
Weighted average exercise price of stock option awards cancelled (in usd per share)	8.62
Weighted average exercise price, ending balance (in usd per share)	$ 9.06

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Share based compensation arrangement by share based payment award options forfeitures in period awards available.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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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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Weighted average price of options that were either forfeited or expired.

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Net number of share options (or share units) granted during the period.

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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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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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

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