Stock-Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Stock-Based Compensation
Stock-based compensation expense	$ 2,400	$ 1,700
Proceeds from exercise of stock options	$ 2,512	$ 4,499
Common Stock
Stock-Based Compensation
Exercise of stock options (in shares)	268,000	540,000
Common Stock \| 2020 Employee stock purchase plan
Stock-Based Compensation
Exercise of stock options (in shares)	300,000	600,000
Proceeds from exercise of stock options	$ 2,500	$ 4,500
2000 Stock Plan
Stock-Based Compensation
Awards granted (in shares)	0
2000 Stock Plan \| Stock Options
Stock-Based Compensation
Options Expiration period	10 years

Represents the number of awards granted in an equity based compensation plan.

No definition available.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Period from grant date that an equity-based award expires, 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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