Percentage of the Fair Value to Determine the price of common stock.

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- Definition

Percentage Of Shareholder Return Award Target

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- Definition

Share based compensation arrangement by share based payment award award measurement period.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Expiration Term

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- Definition

Share based compensation arrangement by share based payment award percentage of shares available for issue.

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No definition available.

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- Definition

Stock Issued During Period Shares Employee Stock Purchase Plans Future Issuance

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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

+ References

No definition available.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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No definition available.

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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

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Percentage of vesting of share-based compensation awards.

+ 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 (a)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&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=6415400&loc=d3e5070-113901

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- Definition

Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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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.

+ 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 (d)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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Employee Benefit Plans - Additional Information 1 (Detail) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate intrinsic value of options exercised	$ 0.7	$ 0.4	$ 0.2
Aggregate intrinsic value of options outstanding	4.4
Aggregate intrinsic value of options exercisable	3.4
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of fair value of common stock, common stock price	85.00%
Shares issued under Employee Stock Purchase Plan	138,831	163,120	151,812
Shares available for equity grants	183,591
Employee Stock Purchase Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares for issuance under Employee Stock Purchase Plan	1,900,000
Employee Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for equity grants	992,666
Description of fair value to determine the price of common stock	Under our equity incentive plans, stock options may be granted to employees, consultants and outside directors to purchase a fixed number of shares of our common stock at prices not less than 100% of the fair market value at the date of grant.
Range of period in which vested stock expire	10 years
Employee Stock Options [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period in which restricted stock unit vest	4 years
Employee Stock Options [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period in which restricted stock unit vest	1 year
Restricted Stock Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period in which restricted stock unit vest	4 years
Restricted Stock Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period in which restricted stock unit vest	1 year
Equity-Based Performance Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period in which restricted stock unit vest	3 years
Award measurement period	1 year
Equity-Based Performance Stock Units [Member] \| Senior Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Rate of shares vest	50.00%
Equity-Based Performance Stock Units [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock granted on achievement of performance goals	150.00%
Equity-Based Performance Stock Units [Member] \| Maximum [Member] \| Senior Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shareholders return adjustment range	125.00%
Equity-Based Performance Stock Units [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock granted on achievement of performance goals	0.00%
Equity-Based Performance Stock Units [Member] \| Minimum [Member] \| Senior Executives [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shareholders return adjustment range	75.00%
Unvested Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Pre-tax unrecognized compensation cost of unvested stock options	1.5
Unvested stock options expected to be recognized weighted-average period	1 year
Unvested Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested stock options expected to be recognized weighted-average period	1 year 7 months 6 days
Pre-tax unrecognized compensation cost of unvested restricted stock units	$ 9.6