Equity (Components Of Accumulated Other Comprehensive Income, Net Of Tax) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Mar. 28, 2021	Mar. 29, 2020	Mar. 28, 2021	Mar. 29, 2020	Dec. 27, 2020	Sep. 27, 2020	Dec. 29, 2019	Sep. 29, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ (7,648.3)	$ (7,532.9)	$ (7,648.3)	$ (7,532.9)	$ (7,904.0)	$ (7,799.4)	$ (6,759.1)	$ (6,231.0)
Net gains/(losses) in AOCI, beginning of period			(364.6)
Other comprehensive income/(loss)	19.6	(134.4)	238.3	(23.3)
Net gains/(losses) in AOCI, end of period	(126.3)		(126.3)
Cumulative effect of adoption of new accounting guidance			(2.2)	17.3
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	2.0	5.6	2.0	5.6	4.1	5.7	3.2	3.9
Net gains/(losses) recognized in OCI before reclassifications	(2.0)	2.5	(2.4)	2.4
Net (gains)/losses reclassified from AOCI to earnings	(0.1)	(0.1)	(1.3)	0.0
Other comprehensive income/(loss)	(2.1)	2.4	(3.7)	2.4
Cumulative effect of adoption of new accounting guidance				(0.7)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(5.7)	(64.8)	(5.7)	(64.8)	(75.5)	(82.1)	33.7	11.0
Net gains/(losses) recognized in OCI before reclassifications	73.3	(96.7)	78.1	(70.9)
Net (gains)/losses reclassified from AOCI to earnings	(3.5)	(1.8)	(1.7)	(7.9)
Other comprehensive income/(loss)	69.8	(98.5)	76.4	(78.8)
Cumulative effect of adoption of new accounting guidance				3.0
Accumulated Net Investment Hedge Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	19.6	47.8	19.6	47.8	(13.5)	11.5	7.7	(10.1)
Net gains/(losses) recognized in OCI before reclassifications	35.6	43.0	13.0	60.7
Net (gains)/losses reclassified from AOCI to earnings	(2.5)	(2.9)	(4.9)	(5.3)
Other comprehensive income/(loss)	33.1	40.1	8.1	55.4
Cumulative effect of adoption of new accounting guidance				2.5
Translation Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(142.2)	(510.4)	(142.2)	(510.4)	(61.0)	(299.7)	(432.0)	(508.1)
Net gains/(losses) recognized in OCI before reclassifications	(81.2)	(78.4)	157.5	(2.3)
Net (gains)/losses reclassified from AOCI to earnings	0.0	0.0	0.0	0.0
Other comprehensive income/(loss)	(81.2)	(78.4)	157.5	(2.3)
Cumulative effect of adoption of new accounting guidance				0.0
Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(7,654.0)	(7,530.1)	(7,654.0)	(7,530.1)	(7,909.7)	(7,805.1)	(6,759.9)	(6,232.2)
Other comprehensive income/(loss)	19.6	(134.4)	238.3	(23.3)
Cumulative effect of adoption of new accounting guidance			(2.2)	17.3
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	(126.3)	(521.8)	(126.3)	(521.8)	$ (145.9)	$ (364.6)	$ (387.4)	$ (503.3)
Net gains/(losses) recognized in OCI before reclassifications	25.7	(129.6)	246.2	(10.1)
Net (gains)/losses reclassified from AOCI to earnings	(6.1)	(4.8)	(7.9)	(13.2)
Other comprehensive income/(loss)	$ 19.6	$ (134.4)	238.3	(23.3)
Cumulative effect of adoption of new accounting guidance			$ 0.0	$ 4.8