Stock-Based Compensation - (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Schedule Of Share Based Compensation Arrangements [Line Items]
Common stock reserved for future issuance	11,900,000
Weighted average remaining contractual term of options outstanding, years price below the market value	6 years	5 years 10 months 24 days
Weighted average remaining contractual term of options exercisable, years	4 years 8 months 12 days	4 years 3 months 18 days
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	3,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost	$ 27.4	$ 17.2	$ 12.5
Total fair market value of all vesting options	13.7	10.5	10.6
Aggregated intrinsic value of options outstanding	353.1
Aggregated intrinsic value of options exercisable	248.5
Aggregated intrinsic value of options exercised	127.1	140.3	57.0
Total income tax benefit recognized for share-based compensation expense	$ 22.0	39.2	16.2
Two Thousand Seventeen Plan
Schedule Of Share Based Compensation Arrangements [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Terms of Award	10
Employee Stock Option
Schedule Of Share Based Compensation Arrangements [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options	$ 38.9	$ 39.7
Unrecognized share-based compensation related to unvested options granted, term	3 years 6 months	3 years 8 months 12 days
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost	$ 13.8	$ 12.0	$ 12.2
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	2,707,000	2,708,000	2,706,000	2,703,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Fair Value at Remeasurement		$ 95.51	$ 95.40
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 95.54	$ 95.51	$ 41.45	$ 41.45
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	7,000	33,000	6,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 99.05	$ 86.42	$ 43.09
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	0	(25,000)	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value	$ 0.00	$ 85.79	$ 0.00
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Exercised in Period	(8,000)	(6,000)	(3,000)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value	$ 88.40	$ 43.09	$ 41.45
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost	$ 0.7	$ 0.5	$ 0.3
Unrecognized share-based compensation related to unvested options granted	$ 0.3	$ 0.3
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms	5 months 1 day	5 months 1 day
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	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	$ 88.34	$ 90.70	$ 0.00
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	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	$ 86.95	$ 90.71
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(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	$ 90.71	$ 90.87
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Exercised in Period	(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	$ 90.70	$ 0.00
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 Compensation Arrangement by Share-based Payment Award, Compensation Cost	$ 12.9	$ 4.7	$ 0.0
Unrecognized share-based compensation related to unvested options granted	$ 27.4	$ 9.3
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms	2 years 1 month 20 days	2 years 6 months
Maximum \| Two Thousand Seventeen 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
Maximum \| Two Thousand Seven 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
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	394,000
2018 Grant [Member] \| 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	0.00
2018 Grant [Member] \| 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	2.00

Schedule Of Share Based Compensation Arrangements [Line Items]

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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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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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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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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Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

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