Stock-Based Compensation - Additional Information (Details)	12 Months Ended
Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for issuance (in shares) \| shares	343,165
Common stock reserved for issuance (in shares) \| shares	2,820,000
Minimum employee tax withholding obligations related to RSUs	$ 6,608,000	$ 7,696,000	$ 6,591,000
Share-based payment arrangement, amount capitalized	$ 0	$ 0	0
Weighted-average remaining contractual term, stock options outstanding	2 months 12 days	9 months 18 days
Aggregate intrinsic value, stock options vested and exercisable	$ 200,000
Intrinsic value, stock options exercised	400,000	$ 6,400,000	3,000,000.0
Cash received from stock option exercises	163,000	$ 726,000	$ 819,000
Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant-date intrinsic value	$ 18,400,000
Share settlement under RSUs (in shares) \| shares	68,625	66,441	41,101
Minimum employee tax withholding obligations related to RSUs	$ 6,500,000	$ 6,900,000	$ 5,300,000
Unamortized stock-based compensation expense	$ 22,300,000	$ 27,800,000
Weighted average remaining amortization period	1 year 2 months 12 days	1 year 3 months 18 days
Restricted stock units (RSUs), performance-based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares) \| shares	68,371	52,960
Period for recognition of compensation expense	3 years
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual life	10 years
Vesting period of stock options	3 years
Minimum \| Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual life	1 year
Maximum \| Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual life	3 years
Common Stock \| Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion ratio	1

Amount of cost capitalized for award under share-based payment arrangement.

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

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement.

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Amount of cash inflow from exercise of option 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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Net number of non-option equity instruments granted to participants.

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Number of shares authorized for issuance under share-based payment arrangement.

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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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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. 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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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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Conversion Of Stock, Conversion Ratio

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Share based compensation arrangement by share based payment award equity instruments other than options grants intrinsic value.

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