Share-Based Compensation - Stock Options Activity (Details) - Stock Option - USD ($)	3 Months Ended	6 Months Ended
Mar. 31, 2021	Jun. 30, 2021	Dec. 31, 2020
Shares
Beginning balance (in shares)	963,726	963,726
Granted (in shares)		269,420
Exercised (in shares)		(98,393)
Forfeited/Expired (in shares)		(32,942)
Ending balance (in shares)		1,101,811
Vested and expected to vest (in shares)		1,044,315
Exercisable (in shares)		526,876
Weighted Average Price
Beginning Balance, Weighted Average Price (in dollars per share)	$ 125.70	$ 125.70
Granted, Weighted Average Price (in dollars per share)		197.28
Exercised, Weighted Average Price (in dollars per share)		108.61
Forfeited, Weighted Average Price (in dollars per share)		117.93
Ending Balance, Weighted Average Price (in dollars per share)		$ 143.63
Weighted-Average Remaining Contractual Term
Stock options outstanding, Weighted-Average Remaining Contractual Term	6 years 11 months 8 days	7 years 3 months 7 days
Aggregate Intrinsic Value
Stock options outstanding, Aggregate intrinsic value		$ 84,203,605	$ 70,829,529
Vested and expected to vest , Weighted Average Price (in dollars per share)		$ 141.56
Exercisable, Weighted Average Price (in dollars per share)		$ 106.77
Weighted-Average Remaining Contractual Term, Vested and expected to vest		7 years 2 months 1 day
Weighted-Average Remaining Contractual Term, Exercisable		5 years 6 months 21 days
Aggregate Intrinsic Value, Vested and expected to vest		$ 81,973,948
Aggregate Intrinsic Value, Exercisable		$ 59,683,365

Share Based Compensation Arrangement By Share Based Payment Award Option Exercised

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- Definition

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

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Granted

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Remaining Contractual Term [Abstract]

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- Definition

Share-based Compensation, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]

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- Definition

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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- Definition

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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- Definition

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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- Definition

Number of fully vested and expected to vest exercisable options that may 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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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 exercise price, at which grantee can acquire shares reserved for issuance, for 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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- Definition

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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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 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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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 for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. 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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