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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.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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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

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

+ References

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

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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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- 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

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Stock-Based Compensation - Narrative (Details) - USD ($) $ in Millions		3 Months Ended
	May 25, 2016	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Stock Based Compensation Details [Line Items]
Shares available for grant (in shares)				74,667,000
Unrecognized compensation costs		$ 2.1
Employee Stock Option
Stock Based Compensation Details [Line Items]
Number of options forfeited (in shares)		113,627
Shares of common stock options outstanding (in shares)		6,105,619		4,352,391
Restricted Stock
Stock Based Compensation Details [Line Items]
Compensation expense		$ 0.1	$ 0.2
RSUs outstanding (in shares)				161,214,000
Unrecognized compensation costs		$ 0.4
Restricted Stock \| Minimum
Stock Based Compensation Details [Line Items]
Vesting period		1 year
Restricted Stock \| Maximum
Stock Based Compensation Details [Line Items]
Vesting period		3 years
Employee Stock Option
Stock Based Compensation Details [Line Items]
Compensation expense		$ 0.3	$ 0.6
Plan 2009
Stock Based Compensation Details [Line Items]
Additional shares authorized (in shares)	2,000,000
Number of options forfeited (in shares)	2,500,000
Plan 2016
Stock Based Compensation Details [Line Items]
Shares approved and authorized (in shares)	4,000,000
Maximum number of shares to any individual (in shares)	1,000,000
Shares of common stock options outstanding (in shares)		131,496		1,394,285,000
Shares available for grant (in shares)		1,363,758		3,113,374
Plan 2016 \| Common Stock
Stock Based Compensation Details [Line Items]
Shares of common stock options outstanding (in shares)		3,164,345
Plan 2016 \| Restricted Stock
Stock Based Compensation Details [Line Items]
RSUs outstanding (in shares)		100,773
Plan 2016, Plan 2009 And Director Plan \| Employee Stock Option
Stock Based Compensation Details [Line Items]
Shares of common stock options outstanding (in shares)		6,105,619		4,352,391,000
Director Plan And The 2009 Plan
Stock Based Compensation Details [Line Items]
Intrinsic value of options outstanding		$ 0.2
Intrinsic value of options exercisable		$ 0.2