Employee service share based compensation recognized period costs capitalized amount.

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- Definition

Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Period for Recognition

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- Definition

Estimated forfeiture rate for unvested options for all non-senior management.

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Estimated forfeiture rate for unvested options for senior management.

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- Definition

Expiration period of stock option plan.

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- Definition

Increase (decrease) in compensation expense due to revised estimated forfeiture rates.

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- Definition

Number of groups within employee population.

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- Definition

Share based compensation arrangement by share based payment award options vested fair value.

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Shares based compensation arrangement by shares based payment award options exercisable intrinsic value.

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- Definition

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

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from severance costs.

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

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Amount of tax benefit for recognition of expense of award 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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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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The weighted average fair value at grant date for nonvested equity-based awards issued 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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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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 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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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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Stock-Based Compensation Expense (Details)	3 Months Ended		6 Months Ended
Stock-Based Compensation Expense (Details)	Jun. 28, 2020 USD ($) group $ / shares shares	Jun. 30, 2019 USD ($) $ / shares	Jun. 28, 2020 USD ($) group $ / shares shares	Jun. 30, 2019 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair values, in dollars per share \| $ / shares	$ 19.13	$ 18.68	$ 18.52	$ 18.59
Total intrinsic value	$ 39,359,000	$ 14,220,000	$ 53,814,000	$ 36,799,000
Total fair values of stock options vest	$ 1,287,000	887,000	$ 37,951,000	$ 30,859,000
Vested (in shares) \| shares				0
Groups within the employee population \| group	2		2
Estimated annual forfeiture rate for unvested options for senior management	7.00%		7.00%
Estimated annual forfeiture rate for unvested options for all other employees	12.00%		12.00%
Increase (decrease) to compensation expense			$ 1,787,000	$ 499,000
Unrecognized compensation expense	$ 65,128,000		$ 65,128,000
Weighted average period to be recognized			2 years
Stock-based compensation expense	8,018,000	10,967,000	$ 22,808,000	23,248,000
Credits related to grants cancelled	1,401,000		1,401,000
Tax benefit from compensation expense	1,277,000	$ 1,813,000	3,841,000	$ 4,035,000
Recognized period costs capitalized	$ 0		$ 0
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant under stock option plans \| shares	16,335,000		16,335,000
Expiration period from grant day			10 years
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for stock option plans			3 years
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in dollars per share) \| $ / shares	$ 56.97		$ 51.53
Vested (in shares) \| shares			0
Granted (in shares) \| shares			432,000	0
Minimum \| General Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for stock option plans			4 years
Maximum \| General Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for stock option plans			5 years