Summary of Significant Accounting Policies - Components of Accumulated Other Comprehensive Income (Loss) (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Sep. 27, 2014	Sep. 28, 2013
Accounting Policies [Abstract]
Minimum pension liability, tax	$ 0.2	$ 0.2

Tax effect of the cumulative change of the minimum pension liability recorded in other comprehensive income (loss).

No definition available.

Name:	holx_AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansTax
Namespace Prefix:	holx_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant