Notes receivable interest rate.

No definition available.

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Namespace Prefix:	geos_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Promissory notes receivable maturity month and year.

+ References

No definition available.

+ Details

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Namespace Prefix:	geos_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
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

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

+ References

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- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

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

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of decrease from sale and reclassification to held-for-sale of financing receivable.

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Balance Type:	credit
Period Type:	duration

- Definition

Amount, before allowance for credit loss, of financing receivable.

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- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Trade Accounts and Financing Receivables - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 2021	Mar. 31, 2020	Mar. 31, 2022	Sep. 30, 2021
Accounts Notes And Loans Receivable [Line Items]
Value of notes with customer	$ 16,106				$ 16,106	$ 7,896
Secured Promissory Note
Accounts Notes And Loans Receivable [Line Items]
Value of notes with customer	$ 8,000	$ 3,700		$ 10,000	$ 8,000
Term of the notes	1 year	9 months	6 months	3 years
Monthly principal and interest payments				$ 300
Frequency of payments				monthly
Manufactured Rental Equipment
Accounts Notes And Loans Receivable [Line Items]
Promissory notes receivable maximum interest rate	9.50%				9.50%
Promissory notes receivable maturity month and year					2023-07
Product
Accounts Notes And Loans Receivable [Line Items]
Partially financed product sale				$ 12,500
Rental Equipment
Accounts Notes And Loans Receivable [Line Items]
Partially financed product sale	$ 10,000