Income Taxes Income before income taxes domestic and foreign (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2017	Oct. 01, 2017	Jul. 02, 2017	Apr. 02, 2017	Jan. 01, 2017	Oct. 02, 2016	Jul. 03, 2016	Apr. 03, 2016	Dec. 31, 2017	Jan. 01, 2017	Jan. 03, 2016
Income (Loss) from Continuing Operations before Income Taxes, Domestic									$ (25,667)	$ (11,002)	$ (18,787)
Income (Loss) from Continuing Operations before Income Taxes, Foreign									4,442	4,709	3,336
Income (loss) before income taxes	$ (23,263)	$ (16,313)	$ (9,247)	$ 27,598	$ (17,396)	$ (4,690)	$ (13,494)	$ 29,287	$ (21,225)	$ (6,293)	$ (15,451)

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(h)(1)(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

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.

+ References

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- Definition

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

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