Business Segments and Geographic Information - Segment Information (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Apr. 01, 2017	Mar. 26, 2016	Apr. 01, 2017	Mar. 26, 2016	Sep. 24, 2016
Segment Reporting Information [Line Items]
Total revenues	$ 715.4	$ 693.3	$ 1,449.8	$ 1,388.4
Operating income (loss)	999.8	136.1	1,145.8	262.1
Depreciation and amortization	95.1	114.0	210.4	229.9
Capital expenditures	25.1	22.0	49.8	41.7
Identifiable assets	8,706.6		8,706.6		$ 7,317.0
Diagnostics
Segment Reporting Information [Line Items]
Total revenues	296.0	304.4	621.3	615.1
Operating income (loss)	929.7	34.3	970.9	65.8
Depreciation and amortization	64.4	83.8	149.3	167.4
Capital expenditures	11.5	13.0	21.8	24.9
Identifiable assets	2,717.7		2,717.7		3,771.9
Breast Health
Segment Reporting Information [Line Items]
Total revenues	280.5	275.8	553.8	537.9
Operating income (loss)	92.7	88.4	177.9	160.0
Depreciation and amortization	4.6	5.1	9.7	12.4
Capital expenditures	1.8	3.4	4.0	5.4
Identifiable assets	813.4		813.4		809.1
GYN Surgical
Segment Reporting Information [Line Items]
Total revenues	101.1	90.9	215.9	189.7
Operating income (loss)	1.8	11.5	27.2	32.3
Depreciation and amortization	23.4	24.8	48.5	49.5
Capital expenditures	3.3	3.4	7.4	6.8
Identifiable assets	1,533.8		1,533.8		1,570.7
Skeletal Health
Segment Reporting Information [Line Items]
Total revenues	21.8	22.2	42.8	45.7
Operating income (loss)	0.1	1.9	(5.7)	4.0
Depreciation and amortization	0.2	0.3	0.4	0.6
Capital expenditures	0.1	0.1	0.4	0.2
Identifiable assets	31.4		31.4		30.9
Medical Aesthetics
Segment Reporting Information [Line Items]
Total revenues	16.0	0.0	16.0	0.0
Operating income (loss)	(24.5)	0.0	(24.5)	0.0
Depreciation and amortization	2.5	0.0	2.5	0.0
Capital expenditures	0.4	0.0	0.4	0.0
Identifiable assets	1,832.3		1,832.3		0.0
Corporate
Segment Reporting Information [Line Items]
Capital expenditures	8.0	$ 2.1	15.8	$ 4.4
Identifiable assets	$ 1,778.0		$ 1,778.0		$ 1,134.4

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-Name Accounting Standards Codification
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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