Consolidated Statements of Income - USD ($) shares in Thousands	12 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 29, 2018
Revenues:
Revenue from product and services	$ 3,776,400,000	$ 3,367,300,000	$ 3,217,900,000
Costs of revenues:
Amortization of intangible assets	253,200,000	318,500,000	319,400,000
Impairment of intangible assets and equipment	25,800,000	578,700,000	0
Gross Profit	2,227,500,000	1,170,900,000	1,696,700,000
Operating expenses:
Research and development	222,500,000	232,200,000	218,700,000
Selling and marketing	484,600,000	564,900,000	544,600,000
General and administrative	356,000,000.0	332,300,000	366,100,000
Amortization of intangible assets	39,700,000	52,000,000.0	59,300,000
Impairment of intangible assets and equipment	4,400,000	106,700,000	46,000,000.0
Impairment of goodwill	0	0	685,700,000
Restructuring and divestiture charges	15,300,000	6,600,000	14,200,000
Operating expenses	1,122,500,000	1,294,700,000	1,934,600,000
Income (loss) from operations	1,105,000,000.0	(123,800,000)	(237,900,000)
Interest income	4,300,000	4,600,000	6,300,000
Interest expense	(116,500,000)	(140,800,000)	(148,700,000)
Debt extinguishment losses	0	(800,000)	(45,900,000)
Other income, net	9,100,000	3,100,000	7,600,000
Income (loss) before income taxes	1,001,900,000	(257,700,000)	(418,600,000)
Benefit for income taxes	(108,600,000)	(54,100,000)	(307,300,000)
Net income (loss)	1,110,500,000	(203,600,000)	(111,300,000)
Net loss attributable to noncontrolling interest	(4,700,000)	0	0
Net income (loss) attributable to Hologic	$ 1,115,200,000	$ (203,600,000)	$ (111,300,000)
Net income (loss) per common share attributable to Hologic:
Basic (in dollars per share)	$ 4.24	$ (0.76)	$ (0.40)
Diluted (in dollars per share)	$ 4.21	$ (0.76)	$ (0.40)
Weighted average number of shares outstanding:
Basic (in shares)	262,727	269,413	275,105
Diluted (in shares)	264,613	269,413	275,105
Product
Revenues:
Revenue from product and services	$ 3,227,000,000.0	$ 2,771,300,000	$ 2,643,900,000
Costs of revenues:
Cost of goods and services sold	953,700,000	948,700,000	886,600,000
Service
Revenues:
Revenue from product and services	549,400,000	596,000,000.0	574,000,000.0
Costs of revenues:
Cost of goods and services sold	$ 316,200,000	$ 350,500,000	$ 315,200,000