Stock Transactions And Stock-Based Compensation (Summary of Share Activity) (Details) - shares shares in Millions		3 Months Ended		9 Months Ended
	Mar. 01, 2019	Oct. 02, 2020	Sep. 27, 2019	Oct. 02, 2020	Sep. 27, 2019
Preferred stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, beginning of period		3.4	1.7	1.7	0.0
Issuance of stock		0.0	0.0	1.7	1.7
Balance, end of period		3.4	1.7	3.4	1.7
Common stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, beginning of period		849.5	834.0	835.5	817.9
Common stock-based award activity		1.1	1.0	3.9	4.1
Common stock issued in connection with LYONs’ conversions		0.0	0.0	0.3	0.9
Issuance of stock	12.1	0.0	0.0	10.9	12.1
Balance, end of period		850.6	835.0	850.6	835.0