Schedule Of Share Based Compensation Arrangements [Line Items]

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Share based compensation arrangement by share based payment award options outstanding weighted average remaining contractual term price below market value.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Exercised in Period

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Fair Value at Remeasurement

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- Definition

Share-based Compensation Arrangement by Share-based payment Award, Equity Instruments Other than Options, Approved by Board

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No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

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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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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

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- Definition

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

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Description of service or performance condition required to be met for earning right to award under share-based payment arrangement. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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- Definition

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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- Definition

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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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. 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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Percentage of vesting of award under share-based payment arrangement.

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Amount of cost expensed and capitalized for award under share-based payment arrangement.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Stock-Based Compensation - (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Schedule Of Share Based Compensation Arrangements [Line Items]
Common stock reserved for future issuance	10,800,000
Weighted average remaining contractual term of options outstanding, years price below the market value	5 years 7 months 6 days	6 years
Weighted average remaining contractual term of options exercisable, years	4 years 3 months 18 days	4 years 8 months 12 days
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights	P3Y	P3Y
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	2,400,000
Share-based Payment Arrangement, Expensed and Capitalized, Amount	$ 39.2	$ 27.4	$ 17.2
Total fair market value of all vesting options	14.2	13.7	10.5
Aggregated intrinsic value of options outstanding	548.6
Aggregated intrinsic value of options exercisable	416.2
Aggregated intrinsic value of options exercised	93.9	127.1	140.3
Total income tax benefit recognized for share-based compensation expense	15.7	22.0	39.2
Employee Stock Option
Schedule Of Share Based Compensation Arrangements [Line Items]
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	$ 44.9
Unrecognized share-based compensation related to unvested options granted, term	2 years 9 months 18 days
Share-based Payment Arrangement, Expensed and Capitalized, Amount	$ 14.8	$ 13.8	$ 12.0
Restricted Stock Units (RSUs)
Schedule Of Share Based Compensation Arrangements [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	2,797,000	2,707,000	2,708,000	2,706,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Fair Value at Remeasurement		$ 95.54	$ 95.51
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 96.85	$ 95.54	$ 95.51	$ 95.40
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	100,000	7,000	33,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 133.57	$ 99.05	$ 86.42
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(3,000)	0	(25,000)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 133.50	$ 0	$ 85.79
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Exercised in Period	(7,000)	(8,000)	(6,000)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	$ 99.05	$ 88.40	$ 43.09
Share-based Payment Arrangement, Expensed and Capitalized, Amount	$ 2.8	$ 0.7	$ 0.5
Unrecognized share-based compensation related to unvested options granted	$ 10.4
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms	3 years 10 months 24 days
Performance Shares
Schedule Of Share Based Compensation Arrangements [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	412,000	313,000	233,000	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 102.22	$ 88.34	$ 90.70	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	128,000	197,000	248,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 133.50	$ 86.95	$ 90.71
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	0	(86,000)	(15,000)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 0	$ 90.71	$ 90.87
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Exercised in Period	(29,000)	(31,000)	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	$ 90.69	$ 90.70	$ 0
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage			20.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period			4 years
Share-based Compensation Arrangement by Share-based payment Award, Equity Instruments Other than Options, Approved by Board			165,000
Share-based Payment Arrangement, Expensed and Capitalized, Amount	$ 21.6	$ 12.9	$ 4.7
Unrecognized share-based compensation related to unvested options granted	$ 37.7
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms	1 year 4 months 24 days
Minimum \| Performance Shares
Schedule Of Share Based Compensation Arrangements [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	128,000
Maximum \| Performance Shares
Schedule Of Share Based Compensation Arrangements [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	256,000	394,000
Maximum \| 2017 Equity Incentive Plan
Schedule Of Share Based Compensation Arrangements [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	5,000,000.0
Maximum \| 2007 Stock Incentive Plan
Schedule Of Share Based Compensation Arrangements [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	5,000,000.0
2018 Grant \| Minimum \| Performance Shares
Schedule Of Share Based Compensation Arrangements [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		0
2018 Grant \| Maximum \| Performance Shares
Schedule Of Share Based Compensation Arrangements [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		2
2019 Grant \| Minimum \| Performance Shares
Schedule Of Share Based Compensation Arrangements [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	0
2019 Grant \| Maximum \| Performance Shares
Schedule Of Share Based Compensation Arrangements [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	2