The number of shares purchased by employees under the Investment Share Purchase Program.

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Annual Vesting Percentage

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Percentage Annual Exercise Price Accretion

+ References

No definition available.

+ Details

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- Definition

Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted AverageFair Value Over Exercise Price

+ References

No definition available.

+ Details

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- Definition

Exercise or strike price stated in the contract for options indexed to the issuer's equity shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(1)
-URI http://asc.fasb.org/extlink&oid=6940734&loc=d3e22047-110879

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 50
-Paragraph 5
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=6445032&loc=d3e90205-114008

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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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

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
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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

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)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ 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)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Balance Type:	na
Period Type:	duration

- Definition

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

+ 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

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

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

+ Details

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Common Stock and Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands					3 Months Ended
	Feb. 23, 2016	Jan. 01, 2016	Mar. 28, 2015	Jan. 01, 2008	Mar. 26, 2016	Mar. 28, 2015	Dec. 26, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise Price Per Share					$ 201.02
Stock option unexercised					1,624,883		1,127,162
Other than options granted in period					27,221
Weighted Average Fair Value					$ 161.39
Stock-based compensation expense					$ 2,686	$ 1,621
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Vesting Period		5 years
Other than options granted in period		8,921
Weighted Average Fair Value		$ 201.91
Investment Share Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Vesting Period					5 years
Shares employees elected to purchase		9,199
Weighted Average Fair Value		$ 91.55
Senior Management \| Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Vesting Period	3 years
Other than options granted in period	9,101
Weighted Average Fair Value	$ 192.26
Chief Executive Officer \| January 1, 2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period				753,864
Shares Vesting Period				5 years
Vesting percentage per year				20.00%
Stock price				$ 42.00
Exercise Price Per Share			$ 198.14		$ 114.35
Stock option unexercised			452,319		301,546	452,319
Chief Executive Officer \| January 1, 2008 \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise Price Per Share				37.65
Chief Executive Officer \| January 1, 2008 \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise Price Per Share				$ 70.00
Chief Executive Officer \| January 1, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period		574,507
Options granted in period, weighted average fair value		$ 39.16
Shares Vesting Period		5 years
Vesting percentage per year		20.00%
Stock price		$ 201.91
Exercise Price Per Share					$ 201.91
Stock option unexercised					574,507
Option exercised, additional percentage		1.50%
Chief Executive Officer \| January 1, 2016 \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise Price Per Share		$ 201.91
Chief Executive Officer \| January 1, 2016 \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period, weighted average fair value of stock over exercise price		$ 150.00
Employee Stock Compensation Plan \| Senior Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period	67,255	663,136
Options granted in period, weighted average fair value	$ 89.21	$ 46.80
Employee Stock Compensation Plan \| Senior Management \| Special long-term service-based retention stock option issued to the Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period		574,507
Employee Stock Compensation Plan \| Senior Management \| Other special long-term service-based retention stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period		70,502
Employee Stock Compensation Plan \| Senior Management \| Performance-Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period		18,127