Details of Finite-lived Intangible Assets by Segment (Detail) - USD ($) $ in Thousands	Jul. 04, 2015	Jan. 03, 2015
Finite-Lived Intangible Assets [Line Items]
Finite Lived, Gross Carrying Amount	$ 8,387
Accumulated Amortization	(4,848)	$ (4,421)
Finite Lived, Net Carrying Amount	3,539	$ 3,966
Thin-film Equipment Segment
Finite-Lived Intangible Assets [Line Items]
Finite Lived, Gross Carrying Amount	7,172
Accumulated Amortization	(4,009)
Finite Lived, Net Carrying Amount	3,163
Photonics
Finite-Lived Intangible Assets [Line Items]
Finite Lived, Gross Carrying Amount	1,215
Accumulated Amortization	(839)
Finite Lived, Net Carrying Amount	$ 376

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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

- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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

- 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.

+ References

No definition available.

+ Details

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

- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=ivac_ThinfilmEquipmentSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=ivac_PhotonicsSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: