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Income Taxes - Tax Reforms (Details) - USD ($) $ in Millions			12 Months Ended
	Jan. 01, 2018	Dec. 31, 2017	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Federal statutory rate (as a percent)		35.00%	35.00%	35.00%	35.00%
Income tax provision			$ 3.6
Accelerated depreciation deductions (as a percent)			100.00%
Accelerated depreciation claimed			$ 2.9
Forecast
Federal statutory rate (as a percent)	21.00%

X

- Definition

The amount of accelerated depreciation claimed, pursuant to Tax Cuts and Jobs Act of 2017.

+ References

No definition available.

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- Definition

Amount of reasonable estimate for income tax expense (benefit) for remeasurement of deferred tax from change in tax rate pursuant to Tax Cuts and Jobs Act of 2017 for which accounting for tax effect is incomplete.

+ References

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- Definition

The percentage of accelerated depreciation deduction, pursuant to Tax Cuts and Jobs Act of 2017.

+ References

No definition available.

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I)
-URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

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