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Share based compensation arrangement by share based payment award grant target performance percentage.

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Share Based Compensation Arrangement By Share Based Payment Award Minimum Employee Subscription Rate

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Share based compensation arrangement by share based payment award number of shares available for future issuance.

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Share based compensation arrangement by share based payment award reduced number of shares available for issuance.

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- Definition

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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Aggregate number of common shares reserved for future issuance.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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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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Discount rate from fair value on offering date that participants pay for shares.

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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).

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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- Definition

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

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

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

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An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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- Definition

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

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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Number of share options (or share units) exercised during the current period.

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Share-based Compensation - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for issuance for each share issued		2
Share-based compensation expense		$ 17,400,000	$ 22,900,000	$ 9,400,000
Income tax benefit recognized related to share-based compensation		$ 900,000	$ 500,000	$ 2,800,000
Share Based compensation award vesting period		3 years
Closing price of common shares		$ 13.66	$ 16.66	$ 11.33
Cash received from exercise of stock options		$ 5,000,000	$ 1,600,000	$ 1,700,000
Tax benefit realized on exercise of stock option		200,000	0	1,300,000
Fair value of options that vested		16,800,000	16,400,000	1,600,000
Income Loss form Discontinued Operations
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		1,200,000
Performance-based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 7,000,000	$ 12,000,000	$ 1,300,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		311,936
Awarded (in shares)		312,000	235,000	835,000
Aggregate grant date fair value of shares vested		$ 6,393,520	$ 2,560,000	$ 0
Time-based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		3,800,000	4,200,000	3,300,000
Fair value of options that vested		$ 3,500,000	$ 4,300,000	$ 12,300,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		207,943
Awarded (in shares)		208,000	135,000	503,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercisable period		7 years 3 months 19 days
Share-based compensation expense		$ 5,300,000	$ 5,500,000	$ 3,700,000
Granted (in shares)		1,182,000	734,000	2,976,000
Granted(in USD per share)		$ 14.67	$ 17.50	$ 11.15
Exercised (in shares)		734,000	169,000	238,000
Board of Directors Chairman [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Plan Modification, Incremental Compensation Cost		$ 5,500,000
2018 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock Capital Shares Reserved for Future issuance		8,000,000
Amended and Restated Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future issuance		2,602,043
Common Stock Capital Shares Reserved for Future issuance		20,000,000
Amended and Restated Equity Plan \| Common Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 1,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		61,736
2010 Equity Incentive Plan \| Time-based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based compensation award vesting period			3 years
2010 Equity Incentive Plan \| Time-based RSUs \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance awards granted		0.00%
2010 Equity Incentive Plan \| Time-based RSUs \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance awards granted		200.00%
Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based compensation award vesting period		3 years
Stock Option Plan \| Certain Employee \| Exercise Price of $9.22
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)		1,182,400
Granted(in USD per share)		$ 14.67
Options granted, estimated fair value		$ 3.87
Stock Option Plan \| Certain Employee \| Exercise Price of $8.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			734,500
Granted(in USD per share)			$ 17.50
Options granted, estimated fair value			$ 4.82
Stock Option Plan \| Certain Employee \| Exercise Price of $9.29
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)				2,975,500
Granted(in USD per share)				$ 11.15
Options granted, estimated fair value				$ 2.84
Stock Option Plan \| Certain Employee \| Exercise Price of $9.29 \| Amended and Restated Equity Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based compensation award vesting period				10 years
Employee Share Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based payment award number of shares authorized	3,000,000
Share-based compensation expense		$ 300,000	$ 100,000	$ 200,000
Share based payment award offering price percentage	90.00%
Payroll deduction to purchase share, Minimum	1.00%
Payroll deduction to purchase share, Maximum	15.00%
Common Stock Capital Shares Reserved for Future issuance		2,675,548