Number Of Stock Incentive Plans

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- Definition

Percentage Of Fair Market Value Of Common Stock

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No definition available.

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- Definition

Purchase plan offering period.

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- Definition

Share based compensation arrangement by share based payment award estimated forfeiture rate.

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No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Increase In Number Of Shares Reserved For Available For Issuance

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No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Maximum Number Of Common Stock Value Per Employee

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No definition available.

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- Definition

Stock option exercise period.

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No definition available.

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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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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.

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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

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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

Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

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

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No definition available.

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Stock-Based Compensation - Additional Information (Details)	12 Months Ended
	Dec. 31, 2018 USD ($) Plans shares	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock incentive plans \| Plans	1
Estimated forfeiture rate	15.00%	14.00%	11.00%
Exercise of Issued Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense \| $	$ 7,700,000
Weighted average period to recognize compensation expense	2 years 3 months 20 days
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense \| $	$ 16,900,000
Weighted average period to recognize compensation expense	2 years 2 months 10 days
Two Thousand Eighteen Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized for issuance under incentive plan (shares)	9,500,000.0
Incentive awards available for grant (shares)	17,600,000
Exercise price fair value	100.00%
Two Thousand Eighteen Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based award vest	25.00%
Restricted stock vesting period	3 years
Two Thousand Eighteen Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price fair value	110.00%
Stock based award vest	33.00%
Restricted stock vesting period	4 years
Term of award	P10Y
Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock authorized for issuance under incentive plan (shares)	8,900,000
Incentive awards available for grant (shares)	10,000,000
Percentage of common stock purchase price	15.00%
Maximum number of common stock shares available for purchase per participant (shares)	50,000
Purchase plan offering period	6 months
Maximum number of common stock value available for purchase per participant \| $	$ 25,000
Increase in number of shares of common stock available for issuance under the purchase plan (shares)	1,000,000
Upon Termination of Retirement [Member] \| Two Thousand Eighteen Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock exercised period	6 months
In the Event of Termination Upon Disability or Death [Member] \| Two Thousand Eighteen Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock exercised period	12 months
In the Event of Termination for all Other Terminations [Member] \| Two Thousand Eighteen Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock exercised period	90 days