Cover Page - shares	9 Months Ended
	Jun. 27, 2020	Jul. 23, 2020
Cover [Abstract]
Title of 12(b) Security	Common Stock, $0.01 par value
Document Transition Report	false
Document Quarterly Report	true
Entity Incorporation, State or Country Code	DE
Entity Address, Postal Zip Code	01752
Entity File Number	1-36214
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 27, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3
Entity Registrant Name	HOLOGIC, INC
Entity Central Index Key	0000859737
Current Fiscal Year End Date	--09-28
Entity Filer Category	Large Accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Common Stock, Shares Outstanding		258,985,242
Entity Shell Company	false
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
City Area Code	(508)
Local Phone Number	263-2900
Entity Tax Identification Number	04-2902449
Entity Address, Address Line One	250 Campus Drive,
Entity Address, City or Town	Marlborough,
Entity Address, State or Province	MA
Trading Symbol	HOLX
Security Exchange Name	NASDAQ