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Common Stock, Shares Reserved For Issuance, Additional Shares

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

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

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Share Based Compensation Arrangement By Share Based Payment Award Percentage Earning Of Participants

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Stock-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options, Employee Stock Purchase Plan Issuance Term

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Aggregate number of common shares reserved for future issuance.

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

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

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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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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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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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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			12 Months Ended
	Jan. 01, 2019	Dec. 29, 2017	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage increase in number of shares available for future issuance under stock based awards			1.00%
Options, grants in period, net of forfeitures (in shares)				0
Weighted average exercise price, granted (USD per share)			$ 3.73
Averages contractual term			10 years
Expected dividend yield			0.00%
Unrecognized compensation cost			$ 0.9
Operating expenses weighted average period			2 years 1 month 17 days
Closing price of the Company's common stock (in USD per share)			$ 1.23
Share based compensation arrangement by share based payment award percentage earning of participants				15.00%
Shares reserved for issuance			18,642,000
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
Equity instruments other than options, outstanding, weighted average grant date fair value (in USD per share)			$ 52.94	$ 52.94
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for issuance			265,000
Additional shares reserved for issuance			150,000
Stock-based compensation arrangement by share-based payment award, equity instruments other than options, employee stock purchase plan issuance term			10 years
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
Options expire from date of grant		10 years
Percentage increase in number of shares available for future issuance under stock based awards		4.00%
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)		1,686,000
Incentive Plan 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options assumed in merger (in shares)		10,171
Subsequent Event \| 2017 Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized (in shares)	1,686,000