Stock-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2022	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Outstanding Stock Options
Beginning balance (in shares)		29,238,432
Granted (in shares)	0	0	0
Exercised (in shares)		(2,776,029)
Forfeited (in shares)		(323,910)
Expired (in shares)		(55,812)
Ending balance (in shares)	26,082,681	26,082,681		29,238,432
Vested and expected to vest (in shares)	26,082,681	26,082,681
Vested and exercisable (in shares)	19,644,436	19,644,436
Weighted Average Exercise Price
Beginning balance (in dollars per share)		$ 0.48
Granted (in dollars per share)		0
Exercised (in dollars per share)		0.37
Forfeited (in dollars per share)		0.57
Expired (in dollars per share)		0.17
Ending balance (in dollars per share)	$ 0.49	0.49		$ 0.48
Vested and expected to vest, weighted average exercise price (in dollars per share)	0.49	0.49
Vested and exercisable, weighted average exercise price (in dollars per share)	$ 0.45	$ 0.45
Stock options additional disclosures
Options outstanding, weighted average contractual life		6 years 8 months 1 day		7 years 4 months 6 days
Vested and expected to vest, weighted average contractual life		6 years 8 months 1 day
Vested and exercisable, weighted average contractual life		6 years 3 months 14 days
Options outstanding, aggregate intrinsic value	$ 16,011	$ 16,011		$ 127,345
Vested and expected to vest, aggregate intrinsic value	16,011	16,011
Vested and exercisable, aggregate intrinsic value	$ 12,893	$ 12,893

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

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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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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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