Stock-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 8.1	$ 9.1	$ 8.6
Income tax benefit recognized	$ 2.8	$ 3.1	$ 3.1
Weighted-average grant-date fair value of option granted (in dollars per share)	$ 8.80	$ 18.45	$ 10.48
Deferred compensation	$ 16.0	$ 13.2
Current deferred compensation	0.9	0.4
Long-term deferred compensation	15.1	12.8
Fair-market valued of price increase or decrease based on common stock	10.6	9.1
Non-vested Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 3.3
Nonvested stock, weighted average recognition period	1 year 3 months 18 days
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (years)	3 years
Unrecognized compensation cost	$ 1.0
Nonvested stock, weighted average recognition period	1 year
Total value of shares vested	$ 0.0	$ 0.2	$ 0.3
Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance (shares)	2.8
Exercised period (years)	10 years
Plan \| Cliff vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (years)	4 years

Deferred Compensation Liability, Fair Value Based on Common Stock

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Share-based Compensation Arrangement by Share-based Payment Award, Award Expiration Period

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable within one year (or the operating cycle, if longer). Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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