Details of Finite-lived Intangible Assets by Segment (Detail) - USD ($) $ in Thousands	Apr. 02, 2016	Jan. 02, 2016
Finite-Lived Intangible Assets [Line Items]
Finite Lived, Gross Carrying Amount	$ 8,387
Accumulated Amortization	(5,488)	$ (5,275)
Finite Lived, Net Carrying Amount	2,899	$ 3,112
Thin-film Equipment Segment
Finite-Lived Intangible Assets [Line Items]
Finite Lived, Gross Carrying Amount	7,172
Accumulated Amortization	(4,570)
Finite Lived, Net Carrying Amount	2,602
Photonics
Finite-Lived Intangible Assets [Line Items]
Finite Lived, Gross Carrying Amount	1,215
Accumulated Amortization	(918)
Finite Lived, Net Carrying Amount	$ 297

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: