Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Oct. 01, 2016	Oct. 03, 2015	Oct. 01, 2016	Oct. 03, 2015	Jan. 02, 2016
Income Tax Disclosure [Abstract]
Gross unrecognized tax benefits	$ 4.3		$ 4.3		$ 2.7
Interest and penalties related to unrecognized tax benefits in noncurrent liabilities	1.2		1.2		$ 0.9
Unrecognized tax benefits, net tax offset	1.4		1.4
Amount, if recognized, that affects the effective tax rate	3.4		3.4
Reduction of unrecognized tax benefit amount	$ 0.8		$ 0.8
Effective tax rate percentage	29.90%	29.40%	28.40%	33.70%

Unrecognized Tax Benefits, Net Tax Offset

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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=6907707&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

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-SubTopic 10
-Section 50
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- Definition

The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6527854

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

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