Share-Based Compensation Arrangement by Share-based Payment Award, Number of Plans

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- Definition

Amount of distribution made to individual in accordance with deferred compensation arrangement.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable after one year (or the operating cycle, if longer).

+ References

No definition available.

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- Definition

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

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

+ References

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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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- Definition

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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- 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.

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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

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- Definition

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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- Definition

Amount of cash paid related to share-based compensation liabilities.

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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

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

Intrinsic value of equity-based compensation awards vested. Excludes stock and unit options.

+ References

No definition available.

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Share-Based Compensation (Narrative) (Details) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 27, 2017 USD ($) plans $ / shares shares	Dec. 28, 2016 USD ($) $ / shares shares	Dec. 30, 2015 USD ($) $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share-based compensation plans \| plans	4
Shares available for grant \| shares	700
Income tax benefits recognized related to share-based compensation	$ 3.3	$ 3.0	$ 2.6
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Contractual life	P10Y
Intrinsic value of the options exercised	$ 2.3	$ 1.4	$ 1.4
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (US$ per share) \| $ / shares	$ 12.59	$ 9.47	$ 11.43
Performance period	3 years
Cash payments	$ 3.9	$ 2.5	$ 3.4
Intrinsic value of shares converted	5.0	3.5	$ 4.9
Accrued compensation included as a component of other current liabilities	0.4	3.9
Accrued compensation included as a component of other noncurrent liabilities	0.4	$ 0.3
Unrecognized compensation cost related to unvested performance share awards outstanding	$ 8.0
Unrecognized compensation cost, expected weighted average period	1 year 8 months 10 days
Stock units outstanding \| shares	1,737	1,366
Restricted stock units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards granted \| shares	100
Weighted average grant date fair value (US$ per share) \| $ / shares	$ 12.04
Performance period	1 year
Unrecognized compensation cost related to unvested performance share awards outstanding	$ 0.5
Unrecognized compensation cost, expected weighted average period	8 months 18 days
Cash payments	$ 0.5
Stock units outstanding \| shares	900	900
Minimum [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target award to be earned (in hundredths)	0.00%
Maximum [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of target award to be earned (in hundredths)	150.00%
Performance shares that vest based on TSR [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards granted \| shares	300
Weighted average grant date fair value (US$ per share) \| $ / shares	$ 13.05
Performance shares that vest based on EBITDA growth [Member] \| Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards granted \| shares	300
Weighted average grant date fair value (US$ per share) \| $ / shares	$ 12.17
2017 Omnibus Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant \| shares	4,300