Fair Value Measurements - Fair Value Assets and Liabilities Measured on Recurring Basis (Detail) $ in Millions	Mar. 27, 2021 USD ($)
Assets:
Assets measured at fair value on a recurring basis	$ 1.1
Liabilities:
Total	99.6
Foreign currency option contracts
Assets:
Assets measured at fair value on a recurring basis	1.1
Contingent consideration
Liabilities:
Contingent consideration	71.7
Interest rate swap
Assets:
Assets measured at fair value on a recurring basis	24.9
Forward foreign currency contracts \| Liability
Assets:
Assets measured at fair value on a recurring basis	3.0
Quoted Prices in Active Market for Identical Assets (Level 1)
Assets:
Assets measured at fair value on a recurring basis	0.0
Liabilities:
Total	0.0
Quoted Prices in Active Market for Identical Assets (Level 1) \| Foreign currency option contracts
Assets:
Assets measured at fair value on a recurring basis	0.0
Quoted Prices in Active Market for Identical Assets (Level 1) \| Contingent consideration
Liabilities:
Contingent consideration	0.0
Quoted Prices in Active Market for Identical Assets (Level 1) \| Interest rate swap
Assets:
Assets measured at fair value on a recurring basis	0.0
Quoted Prices in Active Market for Identical Assets (Level 1) \| Forward foreign currency contracts \| Liability
Assets:
Assets measured at fair value on a recurring basis	0.0
Significant Other Observable Inputs (Level 2)
Assets:
Assets measured at fair value on a recurring basis	0.0
Liabilities:
Total	27.9
Significant Other Observable Inputs (Level 2) \| Foreign currency option contracts
Assets:
Assets measured at fair value on a recurring basis	1.1
Significant Other Observable Inputs (Level 2) \| Contingent consideration
Liabilities:
Contingent consideration	0.0
Significant Other Observable Inputs (Level 2) \| Interest rate swap
Assets:
Assets measured at fair value on a recurring basis	24.9
Significant Other Observable Inputs (Level 2) \| Forward foreign currency contracts \| Liability
Assets:
Assets measured at fair value on a recurring basis	3.0
Significant Unobservable Inputs (Level 3)
Assets:
Assets measured at fair value on a recurring basis	0.0
Liabilities:
Total	71.7
Significant Unobservable Inputs (Level 3) \| Foreign currency option contracts
Assets:
Assets measured at fair value on a recurring basis	0.0
Significant Unobservable Inputs (Level 3) \| Contingent consideration
Liabilities:
Contingent consideration	71.7
Significant Unobservable Inputs (Level 3) \| Interest rate swap
Assets:
Assets measured at fair value on a recurring basis	0.0
Significant Unobservable Inputs (Level 3) \| Forward foreign currency contracts \| Liability
Assets:
Assets measured at fair value on a recurring basis	$ 0.0

No definition available.

Name:	us-gaap_AssetsFairValueDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value of contingent consideration in a business combination that is classified in shareholders' equity.

+ References

+ Details

Name:	us-gaap_ContingentConsiderationClassifiedAsEquityFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fair value of obligations measured on a recurring basis.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisObligations
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

Name:	us-gaap_InvestmentsFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_LiabilitiesFairValueDisclosureAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ForeignExchangeOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=holx_ContingentConsiderationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_InterestRateSwapMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_ForeignExchangeContractMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_LiabilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: