Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Award Types

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- Definition

Share-Based Compensation Arrangement By Share-Based Payment Award, Number Of Tranches

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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-Section S99
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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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.

+ References

No definition available.

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Description of the Business and Summary of Significant Accounting Policies - Stock-based Compensation (Details) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended	12 Months Ended
	Dec. 31, 2017 USD ($) tranche $ / shares shares	Dec. 31, 2018 USD ($) award $ / shares shares	Dec. 31, 2017 USD ($) tranche $ / shares shares	Dec. 31, 2016 $ / shares shares
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of award types \| award		2
One-Tier RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
Two-Tier RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years
Remaining unamortized stock-based compensation \| $		$ 0.1
Unamortized stock-based compensation, requisite service period		2 months 2 days
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		16.2	21.5	16.6
Shares granted (in dollars per share) \| $ / shares		$ 20.26	$ 15.70	$ 15.59
Tranche One \| One-Tier RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		1 year
Tranche One \| Two-Tier RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		1 year
Co-Founder Grants \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining unamortized stock-based compensation \| $	$ 156.2	$ 119.3	$ 156.2
Unamortized stock-based compensation, requisite service period		4 years	5 years 2 months 12 days
Shares granted (in shares)	14.7	14.7	14.7
Number of tranches \| tranche	9		9
Shares granted (in dollars per share) \| $ / shares	$ 10.60
Allocated share-based compensation expense \| $		$ 37.0
Co-Founder Grants \| Tranche One \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Chief Executive Officer \| Co-Founder Grants \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	10.3
Director \| Co-Founder Grants \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)	4.4
Minimum \| Co-Founder Grants \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation, requisite service period			2 years 10 months 24 days
Award requisite period	2 years 10 months 24 days
Maximum \| Co-Founder Grants \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation, requisite service period			6 years 10 months 24 days
Award requisite period	6 years 10 months 24 days