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Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Aggregate Target Payout, If Circumstances Met

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Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Aggregate Target Payout, Performance Percentage

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Share-Based Compensation Arrangement By Share-Based Payment Award, Equity Instruments Other Than Options, Grants In Period, Fair Value

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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

Share-based Compensation Arrangement by Share-based Payment Award, Options, Number of Vesting Installments

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Aggregate number of common shares reserved for future issuance.

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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer).

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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Amount of tax benefit from exercise of option under share-based payment arrangement.

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Amount of cash inflow from exercise of option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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

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Number of shares authorized for issuance under share-based payment arrangement.

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Net 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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- Definition

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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No definition available.

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Percentage of vesting of award under share-based payment arrangement.

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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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Share-Based Compensation - Additional Information (Details)	3 Months Ended	12 Months Ended
	Jun. 27, 2020 USD ($)	Jan. 02, 2021 USD ($) installment $ / shares shares	Dec. 28, 2019 USD ($) $ / shares shares	Dec. 29, 2018 USD ($) $ / shares shares	Dec. 31, 2020 $ / shares	Dec. 27, 2019 $ / shares	Dec. 28, 2018 $ / shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for issuance for each share issued \| shares		2
Share-based compensation expense		$ 22,700,000	$ 12,400,000	$ 17,400,000
Income tax benefit recognized related to share-based compensation		$ 800,000	600,000	900,000
Share-based compensation award vesting period		3 years
Closing price of common shares (in USD per share) \| $ / shares					$ 15.68	$ 13.45	$ 13.66
Number of annual installments \| installment		3
Cash received from exercise of stock options		$ 2,000,000.0	0	5,000,000.0
Tax benefit realized on exercise of stock option		100,000	0	200,000
Fair value of options that vested		15,800,000	19,000,000.0	16,800,000
Board of directors chairman
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense associated with modification			5,500,000
Performance-based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 7,800,000	$ 5,700,000	$ 7,000,000.0
Share-based compensation award vesting period		3 years
Granted (in shares) \| shares		458,000	285,000	312,000
Aggregate grant date fair value of shares vested		$ 14,100,000	$ 5,000,000.0	$ 6,400,000
Performance-based RSUs \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance awards granted		0.00%
Performance-based RSUs \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of performance awards granted		200.00%
Time-based RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 4,900,000	2,100,000	3,800,000
Share-based compensation award vesting period		3 years
Fair value of options that vested		$ 5,100,000	$ 3,200,000	$ 3,500,000
Granted (in shares) \| shares		542,000	216,000	208,000
Time-based RSUs \| Fist Anniversary, Date of Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		33.33%
Time-based RSUs \| Second Anniversary, Date of Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		33.33%
Time-based RSUs \| Third Anniversary, Date of Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage		33.33%
Amended and Restated Equity Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance (in shares) \| shares		20,000,000
Shares available for future issuance \| shares		120,000
Share-based compensation expense		$ 2,900,000
Share-based compensation, liability		2,900,000
Expense associated with modification		$ 5,900,000
Amended and Restated Equity Plan \| Common Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Bonus aggregate target payout, if circumstances met	$ 2,400,000
Bonus aggregate target payout, performance percentage	122.00%
2018 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance (in shares) \| shares		8,000,000
Shares available for future issuance \| shares		6,026,000
Stock Option Plan \| Certain employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares) \| shares		1,053,600	1,138,000	1,182,400
Granted (in USD per share) \| $ / shares		$ 15.48	$ 13.68	$ 14.67
Granted, estimated fair value (in USD per share) \| $ / shares		$ 4.63	$ 3.42	$ 3.87
Stock Option Plan \| Certain employee \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation award vesting period		10 years
Amended And Restated Equity Plan \| Common Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares) \| shares		118,059
Granted, fair value		$ 1,300,000
Employee Share Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance (in shares) \| shares		2,452,739
Share-based compensation expense		$ 300,000	$ 200,000	$ 300,000
Share based payment award number of shares authorized \| shares		3,000,000
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%