Closing price of common stock.

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- Definition

Employee Service Share Based Compensation Unrecognized Compensation Costs

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Employee Service Share Based Compensation Unrecognized Compensation Costs Weighted Average Period Of Recognition

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- Definition

Percentage Increase In Number Of Shares Available For Future Issuance Under Stock Based Awards

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Assumed In Merger

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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- Definition

Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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

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

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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

Net number of share options (or share units) granted during the period.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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

Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended	9 Months Ended		12 Months Ended
	Jan. 01, 2018	Dec. 29, 2017	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, grants in period, net of forfeitures (in shares)			0		0
Weighted average exercise price, granted (USD per share)				$ 3.73
Averages contractual term				10 years
Expected dividend yield				0.00%
Unrecognized compensation cost				$ 1.2
Operating expenses weighted average period				2 years 5 months 16 days
Closing price of the Company's common stock (in USD per share)			$ 1.22	$ 1.22
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instruments other than options, vesting period				3 years
Equity instruments other than options, outstanding, number (in shares)			13,000	13,000		13,000
Equity instruments other than options, outstanding, weighted average grant date fair value (in USD per share)			$ 52.94	$ 52.94		$ 52.94
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average vesting term				6 years
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average vesting term				4 years
2017 Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance (in shares)			381,000	381,000
Options expire from date of grant		10 years
Percentage increase in number of shares available for future issuance under stock based awards		4.00%
Number of additional shares authorized (in shares)	805,000
Options, grants in period, net of forfeitures (in shares)						0
2017 Equity Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock reserved for issuance (in shares)		575,000
Incentive Plan 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options assumed in merger (in shares)		10,171