The number of shares purchased by employees under the investment share purchase program.

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&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://fasb.org/us-gaap/role/ref/legacyRef
-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=109197908&loc=d3e5070-113901

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=109197908&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.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
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- Details

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- Details

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- Details

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- Details

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Common Stock and Share-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands				3 Months Ended
	Mar. 14, 2019	Mar. 01, 2019	Jan. 01, 2019	Mar. 30, 2019	Mar. 31, 2018	Dec. 29, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options granted in period				24,579
Stock option outstanding				348,370		366,829
Stock-based compensation expense				$ 2,066	$ 1,491
Weighted average fair value of stock awards				$ 258.92
Performance-Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option outstanding				65,306
Investment Share Program
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares employees elected to purchase		7,901
Weighted average fair value of stock awards		$ 147.98
Non Employee Director Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period	844
Options granted in period - weighted average fair value	$ 136.10
Employee Stock Compensation Plan \| Senior Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted in period		14,680
Options granted in period - weighted average fair value		$ 136.00
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		4 years	4 years
Other than options granted in period		16,471	207
Weighted average fair value of stock awards		$ 312.56	$ 240.84