Maximum contribution of employees as payroll deductions.

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- Definition

Percentage of market price for stock purchase.

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No definition available.

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- Definition

The minimum grant-date exercise price of incentive stock options granted as a percent of the common stock share price.

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No definition available.

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- Definition

Maximum term of incentive stock options.

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No definition available.

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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 2
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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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- Definition

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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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

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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No definition available.

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- Definition

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

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No definition available.

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- Definition

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

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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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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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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- Definition

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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- Definition

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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- Definition

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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Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units (in shares)		1,044,980	1,102,311
Aggregate intrinsic value of stock options and stock appreciation rights exercised		$ 187.3	$ 0.5	$ 0.4
Unrecognized compensation expense		$ 312.0
Unrecognized compensation expense, recognition period		1 year 3 months 18 days
Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units (in shares)		326,050
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		1 year
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
2015 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance (in shares)		10,900,000
Proposal to increase authorized shares (in shares)		7,100,000
Stock options granted (in shares)		3,363,766
Granted (in usd per share)		$ 38.01
Aggregate intrinsic value of stock options and stock appreciation rights outstanding		$ 427.8
Weighted-average remaining contractual term of stock options and stock appreciation rights outstanding		8 years 6 months
Aggregate intrinsic value of stock options and stock appreciation rights exercisable		$ 55.9
Weighted-average remaining contractual term of stock options and stock appreciation rights exercisable		5 years 9 months 18 days
2015 Plan \| Share-based Payment Arrangement, Option \| Specific Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted (in shares)	1,014,240
Granted (in usd per share)	$ 5.95
2015 Plan \| Share-based Payment Arrangement, Option \| Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted (in shares)	2,501,600
Granted (in usd per share)		$ 19.08
2015 Plan \| Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted (in shares)	192,400
2005 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum term of options and stock appreciation rights		10 years
Minimum grant price, percent of common stock fair value		100.00%
Stock options granted (in shares)		0
Granted (in usd per share)		$ 0
2005 Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		1 year
2005 Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance (in shares)		255,596
Proposal to increase authorized shares (in shares)		600,000
Maximum contribution of employees as payroll deductions		15.00%
Percentage of market price for stock purchase		85.00%