Income Taxes - Components of Income (Loss) From Continuing Operations (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 30, 2017	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Sep. 29, 2018	Sep. 29, 2018	Dec. 29, 2018	Dec. 30, 2017
Income Tax Disclosure [Abstract]
Domestic operations										$ (5,696)	$ 2,553
Foreign operations										479	481
Income from continuing operations before income taxes	$ (172)	$ (904)	$ 937	$ 185	$ 947	$ 1,059	$ 843	$ 33	$ (139)	$ (5,217)	$ 3,034

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

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The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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