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Stock-Based Compensation - Summary of Stock Option Activity and Related Information (Details) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) $ / shares shares
Options Outstanding
Beginning balance (shares) | shares	11,207,931
Granted (shares) | shares	2,237,535
Exercised (shares) | shares	(556,421)
Canceled (shares) | shares	(950,517)
Ending balance (shares) | shares	11,938,528
Vested and expected to vest (shares) | shares	11,584,202
Exercisable (shares) | shares	8,805,571
Weighted-Average Exercise Price per Share
Beginning balance (USD per share) | $ / shares	$ 11.72
Granted (USD per share) | $ / shares	12.29
Exercised (USD per share) | $ / shares	9.03
Canceled (USD per share) | $ / shares	12.14
Ending balance (USD per share) | $ / shares	11.92
Vested and expected to vest (USD per share) | $ / shares	11.88
Exercisable (USD per share) | $ / shares	$ 11.48
Weighted- Average Remaining Contractual Life
Balance (in years)	5 years 9 months 18 days
Vested and expected to vest (in years)	5 years 9 months 18 days
Exercisable (in years)	4 years 10 months 24 days
Aggregate Intrinsic Value
Balance | $	$ 32,384
Vested and expected to vest | $	31,880
Exercisable | $	$ 27,844

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Aggregate Intrinsic Value [Abstract]

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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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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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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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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 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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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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