XML 73 R49.htm IDEA: XBRL DOCUMENT v2.4.1.9
Stock-Based Compensation - Weighted-Average Assumptions Utilized to Value Stock Options (Detail) (Employee Stock Purchase Plan, USD $)
3 Months Ended
Dec. 27, 2014
Dec. 28, 2013
Employee Stock Purchase Plan
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Risk-free interest rate 1.70%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
/ us-gaap_AwardTypeAxis
= holx_EmployeeStockPurchasePlanMember
1.20%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
/ us-gaap_AwardTypeAxis
= holx_EmployeeStockPurchasePlanMember
Expected volatility 38.60%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageVolatilityRate
/ us-gaap_AwardTypeAxis
= holx_EmployeeStockPurchasePlanMember
41.40%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageVolatilityRate
/ us-gaap_AwardTypeAxis
= holx_EmployeeStockPurchasePlanMember
Expected life (in years) 5 years 3 months 3 days 4 years 4 months 24 days
Dividend yield $ 0us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageExpectedDividend
/ us-gaap_AwardTypeAxis
= holx_EmployeeStockPurchasePlanMember
$ 0us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsWeightedAverageExpectedDividend
/ us-gaap_AwardTypeAxis
= holx_EmployeeStockPurchasePlanMember
Weighted average fair value of options granted $ 9.44us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_AwardTypeAxis
= holx_EmployeeStockPurchasePlanMember
$ 7.64us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_AwardTypeAxis
= holx_EmployeeStockPurchasePlanMember