Represents current assets over current liabilities.

No definition available.

Name:	geos_DebtInstrumentCovenantCurrentRatio
Namespace Prefix:	geos_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

Represents EBIT over Interest expense.

+ References

No definition available.

+ Details

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Namespace Prefix:	geos_
Data Type:	xbrli:pureItemType
Balance Type:	na
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- Definition

Amount of minimum consolidated tangible net worth required under the covenant of the debt instrument.

+ References

No definition available.

+ Details

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

- Definition

Amount of minimum liquidity required under the covenant of the debt instrument.

+ References

No definition available.

+ Details

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

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Indicates type of variable interest rate on debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
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-Publisher FASB
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Balance Type:	na
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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

+ Details

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

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Balance Type:	credit
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- Details

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- Details

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Period Type:

- Details

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Note 13 - Long-term Debt (Details Textual) $ in Thousands	Aug. 29, 2025 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Jul. 26, 2023
Long-Term Debt		$ 0	$ 0
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	Secured Overnight Financing Rate (SOFR) [Member]
Line of Credit [Member] \| Woodforest National Bank [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 25,000
Debt Instrument, Basis Spread on Variable Rate	2.75%
Debt Instrument, Covenant, Minimum Consolidated Tangible Net Worth	$ 85,000
Debt Instrument, Covenant, Minimum Liquidity	10,000
Line of Credit [Member] \| Woodforest National Bank [Member] \| Minimum [Member]
Current Ratio				2
Interest Coverage Ratio				1.5
Letter of Credit [Member] \| Woodforest National Bank [Member]
Long-Term Line of Credit	$ 1,000	8,000
Debt Issuance Costs, Gross		$ 400