Business Segments and Geographic Information - Segment Information (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jul. 01, 2017	Jun. 25, 2016	Jul. 01, 2017	Jun. 25, 2016	Sep. 24, 2016
Segment Reporting Information [Line Items]
Total revenues	$ 806.1	$ 717.4	$ 2,255.9	$ 2,105.8
Operating income (loss)	115.0	139.4	1,260.9	401.6
Depreciation and amortization	118.3	120.9	328.7	350.8
Capital expenditures	24.3	21.1	74.0	62.8
Identifiable assets	8,118.0		8,118.0		$ 7,317.0
Diagnostics
Segment Reporting Information [Line Items]
Total revenues	284.1	309.9	905.4	925.0
Operating income (loss)	36.8	31.7	1,007.8	97.6
Depreciation and amortization	64.7	90.6	214.0	258.0
Capital expenditures	13.0	12.7	34.7	37.6
Identifiable assets	2,670.7		2,670.7		3,771.9
Breast Health
Segment Reporting Information [Line Items]
Total revenues	283.7	282.5	837.4	820.5
Operating income (loss)	99.2	90.8	277.1	250.7
Depreciation and amortization	5.0	5.1	14.7	17.5
Capital expenditures	3.2	2.4	7.2	7.7
Identifiable assets	830.0		830.0		809.1
GYN Surgical
Segment Reporting Information [Line Items]
Total revenues	106.5	102.0	322.4	291.6
Operating income (loss)	25.6	16.8	52.9	49.2
Depreciation and amortization	23.7	24.9	72.2	74.4
Capital expenditures	3.5	4.1	10.9	10.9
Identifiable assets	1,512.5		1,512.5		1,570.7
Skeletal Health
Segment Reporting Information [Line Items]
Total revenues	21.8	23.0	64.6	68.7
Operating income (loss)	(1.2)	0.1	(7.0)	4.1
Depreciation and amortization	0.2	0.3	0.5	0.9
Capital expenditures	0.2	0.1	0.5	0.4
Identifiable assets	30.0		30.0		30.9
Medical Aesthetics
Segment Reporting Information [Line Items]
Total revenues	110.0	0.0	126.1	0.0
Operating income (loss)	(45.4)	0.0	(69.9)	0.0
Depreciation and amortization	24.7	0.0	27.3	0.0
Capital expenditures	3.3	0.0	3.7	0.0
Identifiable assets	1,783.7		1,783.7		0.0
Corporate
Segment Reporting Information [Line Items]
Capital expenditures	1.1	$ 1.8	17.0	$ 6.2
Identifiable assets	$ 1,291.1		$ 1,291.1		$ 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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