Senior Secured Convertible Notes and Warrants - Summary of Rollforward Convertible Notes at Fair Value (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Line of Credit Facility [Line Items]
Change in fair value of senior secured convertible notes	$ 3,741	$ 0
Senior Secured Convertible Notes [Member]
Line of Credit Facility [Line Items]
Beginning Balance	0
Issuance of Senior Secured Convertible Notes	1,803
Change in fair value of senior secured convertible notes	2,493
Balance upon modification of senior secured convertible note	4,296
Change in fair value of Senior Secured Convertible Notes	1,248
Ending Balance	$ 5,544	$ 0

Balance upon after modification change in fair value of senior secured convertible notes.

No definition available.

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Period Type:	duration

- Definition

Balance Upon Modification of Senior Secured Convertible Note

+ References

No definition available.

+ Details

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Namespace Prefix:	giga_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Change in fair value of senior secured convertible notes.

+ References

No definition available.

+ Details

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Namespace Prefix:	giga_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Issuance of senior secured convertible notes.

+ References

No definition available.

+ Details

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Namespace Prefix:	giga_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(f))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Fair value portion of notes payable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20,22)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

+ Details

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Balance Type:	credit
Period Type:	instant

- Details

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Period Type: