Employee Benefit Plans and Stock-based Compensation - Summary of Stock Awards Valuation Assumptions (Details) - Employee Stock Purchase Plan - $ / shares	6 Months Ended
Jul. 02, 2018	Jul. 03, 2017
Purchase Period July 3, 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (years)		6 months 1 day
Volatility		41.00%
Risk-free interest rate		1.00%
Expected dividends		0.00%
Estimated weighted average fair value per share at purchase date		$ 1.40
Scenario, Forecast [Member] \| Purchase Period July 2, 2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (years)	6 months 1 day
Volatility	60.00%
Risk-free interest rate	1.70%
Expected dividends	0.00%
Estimated weighted average fair value per share at purchase date	$ 1.34

The weighted average fair value at grant date for nonvested equity-based awards issued 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).

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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.

+ References

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Weighted average expected volatility rate of share-based compensation awards.

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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.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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