Revenue - Additional Information (Detail) $ in Thousands	6 Months Ended
Jun. 27, 2020 USD ($) Installment
Revenue From Contract With Customers [Line Items]
Revenue remaining performance obligation	$ 69,000
TFE
Revenue From Contract With Customers [Line Items]
Revenue remaining performance obligation	$ 14,600
TFE \| Accounts Receivable, Unbilled
Revenue From Contract With Customers [Line Items]
Number of installments \| Installment	3
Change in contract assets	$ (200)
TFE \| Customer Advances
Revenue From Contract With Customers [Line Items]
Contract with customer liability revenue recognized	4,000
TFE \| Deferred Revenue
Revenue From Contract With Customers [Line Items]
Contract with customer liability revenue recognized	55
Photonics
Revenue From Contract With Customers [Line Items]
Change in contract assets	(2,614)
Revenue remaining performance obligation	54,400
Photonics \| Accounts Receivable, Unbilled
Revenue From Contract With Customers [Line Items]
Change in contract assets	$ (2,636)

Notes receivable number of installments.

No definition available.

Name:	ivac_NotesReceivableNumberofInstallments
Namespace Prefix:	ivac_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Revenue From Contract With Customers.

+ References

No definition available.

+ Details

Name:	ivac_RevenueFromContractWithCustomersLineItems
Namespace Prefix:	ivac_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in measure of progress which increases (decreases) right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130551-203045

+ Details

Name:	us-gaap_ContractWithCustomerAssetCumulativeCatchUpAdjustmentToRevenueChangeInMeasureOfProgress
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130549-203045

+ Details

Name:	us-gaap_ContractWithCustomerLiabilityRevenueRecognized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045

+ Details

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

- Details

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

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivablesByBillingStatusTypeAxis=us-gaap_UnbilledRevenuesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=ivac_CustomerAdvancesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BalanceSheetLocationAxis=ivac_DeferredRevenueMember
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: