Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based compensation awards.

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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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Amount of cash outflow to satisfy an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

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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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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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.

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Number of additional shares authorized for issuance under an established share-based compensation plan.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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.

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Percentage of vesting of share-based compensation awards.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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Share-Based Compensation - Additional Information (Detail) - USD ($)				3 Months Ended
	Dec. 14, 2017	Dec. 20, 2012	Dec. 20, 2010	Sep. 28, 2018	Sep. 29, 2017	Nov. 02, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation costs capitalized				$ 0	$ 0
Shares withheld to settle employee minimum statutory obligation for applicable income and other employment taxes				201,877	85,758
Tax withholdings related to net share settlement of restricted share units				$ 8,904,000	$ 3,550,000
Stock Plan 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of additional shares authorized	2,100,000	2,100,000	2,100,000
Ordinary shares available for future grant				1,968,456
Stock Plan 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Ordinary shares available for future grant				14,041
Shares authorized for future issuance						160,000
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award granted vesting period, year				4 years
Options expiration period, year				7 years
Employee Stock Option \| Stock Plan 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense				$ 0
Employee Stock Option \| Vest 12 months after the vesting commencement date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage				25.00%
Employee Stock Option \| Vest monthly over each of the subsequent 36 months
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage				2.083%
Employee Stock Option \| Vest monthly over four years, commencing one month after the vesting commencement date
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage				2.083%
Performance Share Units \| Stock Plan 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units outstanding				455,358
Performance Share Units \| Stock Plan 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units outstanding				97,306
Performance Share Units \| Executive of the Company
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award granted vesting period, year				2 years
Performance Share Units \| Executive of the Company \| Vest at the end of the performance period \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage				0.00%
Performance Share Units \| Executive of the Company \| Vest at the end of the performance period \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage				100.00%
Restricted Share Units \| Stock Plan 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units outstanding				881,146
Unrecognized share-based compensation expense				$ 20,000,000
Unrecognized compensation expense, weighted-average period for recognition				2 years 10 months 24 days
Restricted Share Units \| Stock Plan 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share units outstanding				48,653
Restricted Share Units \| Vesting Option One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award granted vesting period, year				3 years
Restricted Share Units \| Vesting Option Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award granted vesting period, year				4 years
Restricted Share Units \| Non Employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award granted vesting period, year				1 year
Restricted Share Units \| Non Employee Director \| Vest on the first of January
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage				100.00%
Performance Stock Units PSU \| Stock Plan 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense				$ 7,900,000
Unrecognized compensation expense, weighted-average period for recognition				1 year 10 months 24 days