Earnings (Loss) Per Share - Narrative (Details) - Employee stock option and restricted stock units (in shares) - shares shares in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jul. 01, 2018	Jun. 30, 2019	Jul. 01, 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	1,570	1,214	1,631	3,127
Dilutive securities excluded because of net loss				1,921
Impact of dilutive securities excluded because of net loss				823

Shares that would have been included in the diluted earnings per share calculation had the Company not had a net loss during the period.

No definition available.

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- Definition

Shares that would have been included in the calculation of diluted shares had the Company not had a net loss during the period.

+ References

No definition available.

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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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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