Contractual cash interest rate for funds borrowed, under the debt agreement.

No definition available.

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Namespace Prefix:	giga_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents the minimum cumulative revenues that must be achieved to be in compliance with the debt covenants throughout the reporting period.

+ References

No definition available.

+ Details

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Namespace Prefix:	giga_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Contractual deferred interest rate for funds borrowed, under the debt agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	giga_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Maximum amount of the fee to be paid upon maturity under the debt instrument.

+ References

No definition available.

+ Details

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

- Definition

Amount of the remaining fee that accompanies borrowing money under the debt instrument.

+ References

No definition available.

+ Details

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

- Definition

Amount of the remaining fee per month that accompanies borrowing money under the debt instrument.

+ References

No definition available.

+ Details

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

- Definition

Amount of additional capital required to extend the maturity date of the loan.

+ References

No definition available.

+ Details

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

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fee that accompanies borrowing money under the debt instrument.

+ References

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Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of the required periodic payments applied to principal.

+ References

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-Name Accounting Standards Codification
-Topic 210
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 470
-SubTopic 20
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

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-Publisher FASB
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Period Type:	duration

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Note 6 - Term Loan, Revolving Line of Credit and Warrants (Details Textual) - PFG Loan [Member] - USD ($)			1 Months Ended
	Feb. 01, 2020	Jan. 31, 2020	Dec. 29, 2018	Mar. 28, 2020	Dec. 28, 2019	Mar. 30, 2019	Apr. 27, 2017
Debt Instrument, Face Amount							$ 1,500,000
Debt Instrument, Interest Rate, Stated Percentage		16.00%					16.00%
Debt Instrument, Cash Interest Rate		9.50%					9.50%
Debt Instrument, Deferred Interest Rate		6.50%					6.50%
Debt Instrument, Maximum Fee Amount to be Paid upon Maturity							$ 100,000
Debt Instrument, Fee Amount		$ 16,500					76,000
Debt Instrument, Remaining Fee Amount							24,000
Debt Instrument, Remaining Fee Amount, Per Month							$ 1,000
Debt Instrument, Periodic Payment, Principal		$ 57,700	$ 75,000
Debt Instrument, Required Additional Capital To Extend Maturity			$ 500,000
Debt Instrument, Covenant Compliance, Minimum Cumulative Revenue					$ 11,000,000
Repayments of Long-term Debt, Total	$ 75,000
Long-term Debt, Total				$ 792,300		$ 1,800,000