Gross proceeds from registered sale equity securities.

No definition available.

Name:	KOPN_GrossProceedsFromRegisteredSaleEquitySecurities
Namespace Prefix:	KOPN_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Underwriting discounts and offering expenses from sale of equity.

+ References

No definition available.

+ Details

Name:	KOPN_UnderwritingDiscountsAndOfferingExpensesfromSaleofEquity
Namespace Prefix:	KOPN_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

+ Details

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

- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

Name:	us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of consideration received by subsidiary or equity investee in exchange for shares of stock issued or sold. Includes amount of cash received, fair value of noncash assets received, and fair value of liabilities assumed by the investor.

+ References

No definition available.

+ Details

Name:	us-gaap_SaleOfStockConsiderationReceivedPerTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

Name:	us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

Name:	us-gaap_SharesIssuedPricePerShare
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
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_SubsidiarySaleOfStockLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=KOPN_AtTheMarketOfferingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_CommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=KOPN_StifelNicolausAndCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

STOCKHOLDERS’ EQUITY AND STOCK-BASED COMPENSATIO (Details Narrative) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended	6 Months Ended
	Jun. 28, 2021	Mar. 05, 2021	Jun. 26, 2021	Jun. 26, 2021
Subsidiary, Sale of Stock [Line Items]
Shares Issued, Price Per Share			$ 6.74	$ 6.74
Underwriting discounts and offering expenses from sale of equity			$ 0.1	$ 0.5
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount			$ 3.0	$ 3.0
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition				2 years 7 months 6 days
At The Market Offering [Member]
Subsidiary, Sale of Stock [Line Items]
Sale of Stock, Number of Shares Issued in Transaction			100,000	2,500,000
Gross proceeds from registered sale equity securities			$ 0.8	$ 16.8
At The Market Offering [Member] \| Subsequent Event [Member]
Subsidiary, Sale of Stock [Line Items]
Sale of Stock, Number of Shares Issued in Transaction	600,000
Gross proceeds from registered sale equity securities	$ 4.8
Shares Issued, Price Per Share	$ 8.06
Underwriting discounts and offering expenses from sale of equity	$ 0.2
At The Market Offering [Member] \| Common Stock [Member] \| Stifel [Member] \| Minimum [Member]
Subsidiary, Sale of Stock [Line Items]
Sale of Stock, Consideration Received Per Transaction		$ 50.0