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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- Definition

Number of common shares reserved for future issuance related to deferred compensation arrangements with individuals.

+ References

No definition available.

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- 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.

+ References

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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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No definition available.

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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.

+ References

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-Publisher FASB
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- References

No definition available.

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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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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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).

+ References

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-Topic 718
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-Section 50
-Paragraph 2
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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Percentage of vesting of share-based compensation awards.

+ References

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-Topic 718
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- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ References

No definition available.

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Share-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	3 Months Ended		9 Months Ended
	Sep. 26, 2018	Sep. 27, 2017	Sep. 26, 2018	Sep. 27, 2017
Total share-based compensation [Abstract]
Total share-based compensation	$ 1,100	$ 2,493	$ 3,661	$ 6,546
Performance share units [Member]
Total share-based compensation [Abstract]
Total share-based compensation	$ 902	2,246	$ 2,922	6,090
Restricted Stock Units [Abstract]
Performance period, equity award			3 years
Common stock shares issued (in shares)			0.2
Common stock shares deferred (in shares)	0.3		0.3
Shares paid for tax withholding (in shares)			0.1
Unrecognized compensation cost [Abstract]
Unrecognized compensation cost related to unvested share awards outstanding	$ 9,300		$ 9,300
Unrecognized compensation cost, expected weighted average period			1 year 1 month 27 days
Performance share units [Member] \| Minimum [Member]
Restricted Stock Units [Abstract]
Percentage of target awards to be earned (in hundredths)			0.00%
Performance share units [Member] \| Maximum [Member]
Restricted Stock Units [Abstract]
Percentage of target awards to be earned (in hundredths)			150.00%
Performance share units [Member] \| Performance share units that vest based on TSR [Member]
Restricted Stock Units [Abstract]
Equity awards granted (in shares)			0.2
Equity awards, grant date fair value (in dollars per share)			$ 18.17
Performance share units [Member] \| Performance share units that vest based on Adjusted EPS growth [Member]
Restricted Stock Units [Abstract]
Equity awards granted (in shares)			0.3
Equity awards, grant date fair value (in dollars per share)			$ 15.93
Restricted stock units for board members [Member]
Total share-based compensation [Abstract]
Total share-based compensation	198	$ 247	$ 739	$ 456
Restricted Stock Units [Abstract]
Equity awards granted (in shares)			0.1
Equity awards, grant date fair value (in dollars per share)			$ 15.50
Performance period, equity award			1 year
Common stock shares issued (in shares)			0.2
Unrecognized compensation cost [Abstract]
Unrecognized compensation cost related to unvested share awards outstanding	$ 600		$ 600
Unrecognized compensation cost, expected weighted average period			7 months 20 days