Share-Based Compensation Arrangement By Share-Based Payment Award, Award Vesting Period, Number Of Installments

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Consecutive Offering Period

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Maximum Employee Subscription Amount

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Consecutive Offering Periods

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Purchase Periods

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Purchase Period

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- Definition

Share-Based Compensation Arrangement By Share-based Payment Award, Annual Percentage Of Additional Shares Authorized

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- Definition

Share-Based Compensation Arrangement By Share-based Payment Award, Minimum Employee Subscription Rate

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- Definition

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

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Aggregate number of common shares reserved for future issuance.

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- Definition

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

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

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Amount of noncash expense for award of restricted stock or unit under share-based payment arrangement.

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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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- 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

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

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- Definition

Number of 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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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

Price of a single share of a number of saleable stocks of a company.

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- Definition

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

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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

Purchase price of common stock expressed as a percentage of its fair value.

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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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Stock-Based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands			12 Months Ended
	Dec. 05, 2018 USD ($) purchase_period offering shares	Nov. 30, 2018 shares	Dec. 31, 2020 USD ($) installment $ / shares shares	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares authorized for issuance (in shares) \| shares			64,200,000
Total intrinsic value of options exercised (less than for the year ended December 31, 2017)			$ 785,700	$ 75,600	$ 5,300
Consideration for options exercised			179,600
Restricted stock unit			5,000	5,500	0
Compensation costs			93,021	81,122	72,565
Total unrecognized compensation cost related to non-vested stock-based compensation			$ 226,800
Weighted-average period of cost expected to be recognized			2 years 10 months 24 days
Service-based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			4 years
Service-based awards \| Twelve months of continued employment or service
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			12 months
Vesting percentage			25.00%
Service-based awards \| Following twelve quarters
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			36 months
Number of installments \| installment			12
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares authorized for issuance (in shares) \| shares			36,300,000
Compensation costs			$ 77,748	74,780	63,288
Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs			2,872	1,217	0
Performance-based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs			$ 9,600	$ 9,800	$ 10,600
2018 Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares authorized for issuance (in shares) \| shares		13,000,000
Annual percentage increase of shares reserved and available for issuance		4.00%
Shares available for future grant (in shares) \| shares			27,900,000
2016 Equity Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period			10 years
ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share available for future issuance (in shares) \| shares			3,600,000
ESPP \| Employee stock purchase plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares authorized for issuance (in shares) \| shares	810,000
Offering period \| offering	1
Purchase period \| purchase_period	1
Purchase price at which shares are sold, percent	85.00%
Minimum percentage of compensation through payroll deductions	1.00%
Maximum percentage of compensation through payroll deductions	50.00%
Maximum shares to be purchased during purchase period (in shares) \| shares	3,000
Maximum value of shares to be purchased during purchase period	$ 25,000
Purchase of common stock under employee stock purchase plan (in shares) \| shares			251,752
Weighted average fair value per share (usd per share) \| $ / shares			$ 27.97
Share-Based Compensation Arrangement By Share-Based Payment Award, Purchase Period	6 months
Share-Based Compensation Arrangement By Share-Based Payment Award, Consecutive Offering Period	6 months