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

No definition available.

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

+ Details

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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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

+ Details

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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.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Description of the Business and Summary of Significant Accounting Policies - Stock-based Compensation (Details) shares in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Dec. 31, 2017 shares	Mar. 31, 2019 award shares	Dec. 31, 2018 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
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted (in shares)		2.3
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]
Shares granted (in shares)	14.7	14.7	14.7
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