Actual percentage achieved.

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The number of shares under a share-based award plan other than a stock option that were achieved during the reporting period due to the approval of the actual performance achievement of participants.

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Maximum target percentage allowed under grant.

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Period over which plan activity is adjusted to determine the maximum number of shares that may be issued in accordance with the plan.

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Share-based Compensation Arrangement by Share-based Payment Award, Performance Measurement Period

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Total term (in years) over which a stock option may be exercised, before it is expired.

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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.

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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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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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No definition available.

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Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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

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Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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).

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The weighted average fair value at grant date for nonvested equity-based awards issued 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).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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.

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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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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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No definition available.

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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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Gross number of share options (or share units) granted during the period.

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No definition available.

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Number of options outstanding, including both vested and non-vested options.

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Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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No definition available.

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Number of share options (or share units) exercised during the current period.

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Stock-Based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Jan. 03, 2016	Dec. 28, 2014	Dec. 29, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Plan activity adjustment period	5 years
Number of shares available for grant (in shares)	2,738,086
Tax benefit	$ 3.0	$ 2.9	$ 2.3
Award vesting period	3 years
Term to exercise stock option before expiration (not more than)	10 years
Grants in period (in shares)	0	0	0
Outstanding (in shares)	12,000	33,000
Unrecognized compensation cost, unvested stock options	$ 0.0
Exercises in period (in shares)	0	0	0
Windfall
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess tax benefit from share-based compensation, financing activities	$ 0.2	$ 0.4	$ 0.5
Non-Employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding (in shares)	12,000
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation cost not yet recognized, period for recognition	2 years
Granted (in shares)	375,000
Maximum target percentage allowed under grant	200.00%
Performance Shares, Financial Goals
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, unvested restricted stock	$ 3.3
Weighted average grant date fair value (in dollars per share)	$ 16.31
Total nonvested shares (in shares)	287,896
Granted (in shares)	250,000
Maximum target percentage allowed under grant	200.00%
Performance measurement period	1 year
Additional requisite service period	2 years
Actual percentage achieved	115.00%
Actual shares achieved	287,896
Performance Shares, Total Shareholder Return
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, unvested restricted stock	$ 1.4
Granted (in shares)	125,000
Maximum target percentage allowed under grant	200.00%
Performance measurement period	3 years
Performance Shares, Total Shareholder Return \| Monte Carlo Fair Value
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)	$ 16.01
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost, unvested restricted stock	$ 12.0
Compensation cost not yet recognized, period for recognition	2 years
Weighted average grant date fair value (in dollars per share)	$ 16.30	$ 16.47
Grants in period (in dollars per share)	$ 15.85	$ 15.63	$ 19.74
Vested in period, fair value	$ 5.4	$ 7.1	$ 6.5
Total nonvested shares (in shares)	885,882	1,192,550
Granted (in shares)	320,357
Award vesting period	4 years
Stock-based compensation cost
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation cost	$ 7.9	$ 7.6	$ 6.0
Class A common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares available for grants	15.00%
Maximum shares eligible to earn [Member] \| Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	750,000
Maximum shares eligible to earn [Member] \| Performance Shares, Total Shareholder Return
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total nonvested shares (in shares)	250,000