Share-Based Compensation Arrangement By Share Based Payment Award, Options Pre-Vesting Forfeitures Estimated

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- Definition

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

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- Definition

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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- Definition

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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- 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.

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- Definition

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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- Definition

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

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Share-Based Compensation - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 03, 2020	Jun. 28, 2019	Jul. 03, 2020	Jun. 28, 2019	Dec. 31, 2019
Amended And Restated Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate of common stock available for grant	17,300,000		17,300,000		25,500,000
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized share-based compensation expense on non-vested stock options	$ 90.9		$ 90.9
Period For Recognition (in years)			1 year 7 months 6 days
Options pre-vesting forfeitures estimated	5.00%	5.00%	5.00%	5.00%
Service Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum award vesting period (in years)			3 years
Performance or Market Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum award vesting period (in years)			2 years
Employee Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercised during period (in shares)	0		0
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate of common stock available for grant	3,600,000		3,600,000		4,800,000