Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2023	Mar. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Guarantee balance for project implementation fees	$ 3.8	$ 4.2

Guarantee balance for project implementation fees.

No definition available.

Name:	giga_GuaranteeBalanceForProjectImplementationFees
Namespace Prefix:	giga_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant