Common Stock, Capital Shares Reserved for Future Issuance, Additional Shares Reserved, Maximum

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- Definition

Common Stock, Capital Shares Reserved for Future Issuance, Additional Shares Reserved, Percentage, Maximum

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

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 cost to be recognized for option under share-based payment arrangement.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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

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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- Definition

Percentage of vesting of award under share-based payment arrangement.

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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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Stockholders' Equity - Stock-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2019	Jan. 01, 2019
Stock Options
Unearned stock-based compensation	$ 72.4
Weighted average recognition period	2 years 9 months 18 days
Options
Stock Options
Contractual life of stock options	10 years
Options \| Directors \| Minimum
Stock Options
Service period	1 year
Options \| Directors \| Maximum
Stock Options
Service period	3 years
Options \| Vesting after first year of service
Stock Options
Service period	4 years
Percentage of shares to vest	25.00%
Options \| Vesting in years two through four
Stock Options
Vesting period	36 months
Stock Incentive Plan 2018
Stock Options
Number of shares reserved for issuance (in shares)	3,381,983	1,386,809
Number of additional shares reserved for issuance, maximum (in shares)			739,631
Number of additional shares reserved for issuance, percentage, maximum			4.00%
Number of shares available for issuance (in shares)	1,358,694