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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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Business Segments and Geographic Information - Segment Information (Detail) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Sep. 30, 2017	Jul. 01, 2017	Apr. 01, 2017	Dec. 31, 2016	Sep. 24, 2016	Jun. 25, 2016	Mar. 26, 2016	Dec. 26, 2015	Sep. 30, 2017	Sep. 24, 2016	Sep. 26, 2015
Segment Reporting Information [Line Items]
Total revenue	$ 802.9	$ 806.1	$ 715.4	$ 734.4	$ 726.8	$ 717.4	$ 693.3	$ 695.2	$ 3,058.8	$ 2,832.7	$ 2,705.0
Operating income									1,370.2	548.6	455.1
Depreciation and amortization									449.2	465.4	491.4
Capital expenditures									107.6	94.5	89.4
Identifiable assets	7,979.6				7,317.0				7,979.6	7,317.0	7,642.5
Corporate
Segment Reporting Information [Line Items]
Capital expenditures									21.0	12.3	11.1
Identifiable assets	1,262.7				1,134.4				1,262.7	1,134.4	1,087.9
Diagnostics
Segment Reporting Information [Line Items]
Total revenue									1,197.1	1,236.9	1,211.8
Operating income									1,054.2	126.0	109.5
Depreciation and amortization									278.9	341.8	358.7
Capital expenditures									50.9	53.5	55.6
Identifiable assets	2,621.6				3,771.9				2,621.6	3,771.9	4,055.8
Breast Health
Segment Reporting Information [Line Items]
Total revenue									1,138.3	1,112.8	1,063.4
Operating income									373.4	350.5	296.3
Depreciation and amortization									19.7	22.6	28.6
Capital expenditures									12.0	10.6	12.8
Identifiable assets	824.0				809.1				824.0	809.1	815.4
Medical Aesthetics
Segment Reporting Information [Line Items]
Total revenue									207.5	0.0	0.0
Operating income									(115.9)	0.0	0.0
Depreciation and amortization									54.2	0.0	0.0
Capital expenditures									7.3	0.0	0.0
Identifiable assets	1,751.2				0.0				1,751.2	0.0	0.0
GYN Surgical
Segment Reporting Information [Line Items]
Total revenue									427.1	393.1	335.8
Operating income									65.0	69.1	38.6
Depreciation and amortization									95.7	99.9	102.7
Capital expenditures									15.2	17.7	9.5
Identifiable assets	1,494.6				1,570.7				1,494.6	1,570.7	1,658.1
Skeletal Health
Segment Reporting Information [Line Items]
Total revenue									88.8	89.9	94.0
Operating income									(6.5)	3.0	10.7
Depreciation and amortization									0.7	1.1	1.4
Capital expenditures									1.2	0.4	0.4
Identifiable assets	$ 25.5				$ 30.9				$ 25.5	$ 30.9	$ 25.3