Employee Stock Purchase Plan, Purchase Discount, Percent

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- Definition

Employee Stock Purchase Plan, Shares Authorized for Purchase

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- Definition

Employee Stock Purchase Plan, Shares Reserved for Future Issuance

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Exercise Price, Required Percentage of Fair Market Value

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- Definition

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

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- Definition

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

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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

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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- Definition

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

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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

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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- Definition

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

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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

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

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

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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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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Share-Based Compensation - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	May 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price required percentage of fair market value	100.00%
Award vesting period	4 years
Intrinsic value of options exercised	$ 121,500,000	$ 38,600,000	$ 18,800,000
Cash received from exercise of stock options	45,900,000	8,500,000	9,700,000
Fair value of options vested	52,100,000	20,400,000	8,200,000
Compensation cost not yet recognized	$ 61,400,000
Compensation cost not yet recognized, period for recognition	1 year 2 months 12 days
Capitalized costs	$ 0	$ 0	$ 0
Tax benefit from compensation expense	$ 0
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	4 years
Compensation cost not yet recognized	$ 31,400,000
Compensation cost not yet recognized, period for recognition	1 year 8 months 12 days
Fair value of equity instruments other than options that vested during the period	$ 100,000
2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares authorized (shares)		2,500,000
Authorized amount for issuance (shares)	1,500,000
Stock option contractual terms	10 years
Stock authorized for purchase (shares)				$ 25,000
Purchase discount (as a percent)				85.00%
Stock reserved for future issuance (shares)				300,000
Issuance of common stock from ESPP (shares)	171,564
Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized amount for issuance (shares)	0
Stock option contractual terms	7 years
Inducement Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Option, Exercise Price Range, Shares Outstanding	246,728	417,343