Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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-Section 50
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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

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

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Purchase price of common stock expressed as a percentage of its fair value.

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Employee Benefit Plans (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 03, 2021	Sep. 27, 2020	Oct. 03, 2021	Sep. 27, 2020
A2016 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for future grant (in shares)	1,800,000		1,800,000
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for future grant (in shares)	200,000		200,000
Maximum percentage of compensation contributed by employees (in percentage)	10.00%		10.00%
Purchase percentage of stock at fair market value (in percentage)			85.00%
Options and RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting term			4 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting term			3 years
Purchase rights granted			152,000
Performance Shares \| Minimum \| Target Shares Granted
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage vest of performance shares			0.00%
Performance Shares \| Maximum \| Target Shares Granted
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage vest of performance shares			150.00%
Share-based Payment Arrangement, Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option granted	0	0	0	0
Total unrecognized compensation	$ 1.2		$ 1.2
Weighted-average period of recognition of stock based compensation			1 year 6 months
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Purchase rights granted			731,000
Total unrecognized compensation	$ 42.4		$ 42.4
Weighted-average period of recognition of stock based compensation			2 years 7 months 6 days