Employee contributions vested, percentage.

No definition available.

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- Definition

Employer Contributions, Percent Vested Annually

+ References

No definition available.

+ Details

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- Definition

The vesting period for discretionary employer contributions, which vest ratably on an annual basis.

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No definition available.

+ Details

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- Definition

Cash surrender value of group life insurance contracts at the balance sheet date.

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No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Maximum employee contributions from annual bonus percentage to dcp.

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No definition available.

+ Details

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Namespace Prefix:	holx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum employee contributions from base salary percentage to dcp.

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No definition available.

+ Details

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Namespace Prefix:	holx_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Nonqualified deferred compensation plan annual contribution.

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No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Details

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- Details

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- Details

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Deferred Compensation Plan - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2017	Sep. 24, 2016	Sep. 26, 2015
Gen-Probe Incorporated [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Compensation expense for the DCP discretionary contributions	$ 43.2	$ 37.0
Nonqualified Deferred Compensation Plan [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Maximum employee contributions from base salary, percentage	75.00%
Maximum employee contributions from annual bonus, percentage	100.00%
Employee contributions vested, percentage	100.00%
Percent vested annually	33.33%
Contributions, vesting period, years	3 years
Compensation expense for the DCP discretionary contributions	$ 3.4	3.1	$ 1.8
Investment in group life insurance contracts	$ 41.0	$ 36.0
Nonqualified Deferred Compensation Plan [Member] \| One Third Annually [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Contributions, vesting period, years	3 years