Business Segments and Geographic Information - Segment Information (Detail) (USD $)
3 Months Ended 6 Months Ended
Mar. 28, 2015
Mar. 29, 2014
Mar. 28, 2015
Mar. 29, 2014
Sep. 27, 2014
Segment Reporting Information [Line Items]          
Total revenues $ 655,500,000 $ 625,000,000 $ 1,308,300,000 $ 1,237,400,000  
Operating income (loss) 109,800,000 50,200,000 213,300,000 111,500,000  
Depreciation and amortization 126,600,000 130,000,000 248,600,000 257,900,000  
Capital expenditures 18,700,000 21,300,000 39,700,000 37,800,000  
Identifiable assets 8,031,800,000   8,031,800,000   8,414,700,000
Diagnostics          
Segment Reporting Information [Line Items]          
Total revenues 296,700,000 290,800,000 600,800,000 576,500,000  
Operating income (loss) 27,100,000 15,200,000 55,300,000 20,000,000  
Depreciation and amortization 91,900,000 94,600,000 180,500,000 186,800,000  
Capital expenditures 11,400,000 14,800,000 26,200,000 25,100,000  
Identifiable assets 4,208,200,000   4,208,200,000   4,383,500,000
Breast Health          
Segment Reporting Information [Line Items]          
Total revenues 255,500,000 238,700,000 497,500,000 465,200,000  
Operating income (loss) 75,400,000 25,800,000 135,900,000 69,700,000  
Depreciation and amortization 8,300,000 9,200,000 15,900,000 18,500,000  
Capital expenditures 3,000,000 2,300,000 5,500,000 4,100,000  
Identifiable assets 838,000,000   838,000,000   859,800,000
GYN Surgical          
Segment Reporting Information [Line Items]          
Total revenues 79,100,000 72,000,000 163,500,000 150,900,000  
Operating income (loss) 4,500,000 6,600,000 17,700,000 17,700,000  
Depreciation and amortization 26,000,000 26,000,000 51,500,000 52,100,000  
Capital expenditures 2,400,000 2,200,000 4,400,000 4,000,000  
Identifiable assets 1,698,200,000   1,698,200,000   1,748,200,000
Skeletal Health          
Segment Reporting Information [Line Items]          
Total revenues 24,200,000 23,500,000 46,500,000 44,800,000  
Operating income (loss) 2,800,000 2,600,000 4,400,000 4,100,000  
Depreciation and amortization 400,000 200,000 700,000 500,000  
Capital expenditures 100,000 0 200,000 200,000  
Identifiable assets 24,000,000   24,000,000   26,100,000
Corporate          
Segment Reporting Information [Line Items]          
Capital expenditures 1,800,000 2,000,000 3,400,000 4,400,000  
Identifiable assets $ 1,263,400,000   $ 1,263,400,000   $ 1,397,100,000