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Income Taxes (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 29, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Sep. 30, 2017 | Sep. 29, 2018 | Sep. 30, 2017 | Dec. 30, 2017
Income Taxes |  |  |  |  |  |  |
Remeasurement of deferred tax balances |  |  |  |  | $ 0.3 |  |
Federal statutory rate (as a percent) |  |  |  |  | 21.00% |  |
Amount of provisional income tax |  | $ 0.2 |  |  |  |  | $ 3.6
Adjustment to provisional amounts recorded at December 30, 2017 |  |  | $ 0.1 |  |  |  |
Effective tax rate (as a percent) | 20.90% |  |  | 41.70% | 24.10% | 38.00% | 22.70%

X
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 Reference 2: 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)(2)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 3: 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 + Details
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