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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Topic 718
-SubTopic 10
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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

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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.

+ References

No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

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Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended
	Feb. 15, 2017	Apr. 02, 2017	Apr. 03, 2016
Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	248,400
Compensation expense		$ 2.9	$ 1.3
Related tax benefit		$ 1.1	$ 0.5
Performance Shares, Financial Goals
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	165,600
Weighted average grant date fair value (in dollars per share)	$ 21.07	$ 20.98
Award vesting period	3 years
Performance Shares, Total Shareholder Return (TSR)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	82,800
Award vesting period	3 years
Monte Carlo Fair Value \| Performance Shares, Total Shareholder Return (TSR)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)	$ 20.16
Maximum shares eligible to earn \| Performance shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	496,800
Maximum target percentage allowed under grant	200.00%