Reporting Segment And Geographic Information (Reconciliation Of The Company's Consolidated Segment Operating Income To Consolidated Income Before Income Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
Jan. 01, 2021	Jan. 03, 2020	Dec. 28, 2018
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated operating income	$ 419.8	$ 375.9	$ 320.7
Unallocated corporate expense	(1,335.1)	(1,405.0)	(1,360.3)
Acquired deferred revenue adjustment	(4.3)	(7.0)	(23.6)
Amortization of acquired capitalized commissions	5.5	6.3	4.7
Amortization of purchased intangible assets	(157.8)	(167.8)	(179.6)
Amortization of acquisition-related inventory step-up	0.0	0.0	(0.2)
Acquisition / divestiture items	(21.4)	(20.5)	(38.9)
Stock-based compensation / deferred compensation	(90.4)	(81.2)	(75.7)
Restructuring charges / executive transition costs	(28.2)	(27.9)	(8.7)
COVID-19 expenses	(3.2)	0.0	0.0
Total non-operating expense, net	(24.8)	(31.1)	(42.7)
Consolidated income before taxes	395.0	344.8	278.0
Segments Revenue
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated operating income	793.6	747.1	734.6
Non-Segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Unallocated corporate expense	$ (74.0)	$ (73.1)	$ (91.9)

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Share-Based Payment Arrangement And Deferred Compensation Arrangement With Individual, Compensation Expense

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The amount of expense recognized in the current period for the periodic realization of capitalized fees that were paid to salespeople, distributors, brokers, and agents at the time of the conclusion of the sale. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

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Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration from customer has been received or is due, from business combination.

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Amount of income (loss) from continuing operations before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of income (loss) from equity method investments.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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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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