Represents period for adjustments from purchase holdback liability for asset acquisition.

No definition available.

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Namespace Prefix:	gnss_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the amount of holdback liability deposited in asset acquisition.

+ References

No definition available.

+ Details

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Namespace Prefix:	gnss_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents number of shares of equity interest issued or issuable for business acquisition each anniversaries.

+ References

No definition available.

+ Details

Name:	gnss_BusinessAcquisitionEquityInterestIssuedOrIssuableNumberOfSharesEachAnniversaries
Namespace Prefix:	gnss_
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Balance Type:	na
Period Type:	duration

- Definition

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

+ Details

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Balance Type:	na
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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

+ Details

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=123586518&loc=d3e1043-128460

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

- Definition

Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
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-SubTopic 30
-Section 30
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of shares of stock issued during the period pursuant to acquisitions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-Topic 505
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Note 4 - Business Combinations (Details Textual) $ / shares in Units, $ in Thousands, $ in Millions				3 Months Ended						12 Months Ended
	Jun. 07, 2021 USD ($) $ / shares shares	Oct. 02, 2020 USD ($) $ / shares shares	Oct. 02, 2020 CAD ($) shares	Sep. 30, 2021 USD ($) $ / shares	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 30, 2020 USD ($)
Share Price (in dollars per share) \| $ / shares	$ 5.05	$ 5.98		$ 5.18						$ 5.18
Zonehaven, Inc [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares) \| shares	2,165,824
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	$ 10,938									$ 10,938	$ (0)
Business Combination, Acquisition Related Costs										$ 140
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)	6 years 8 months 12 days
Zonehaven, Inc [Member] \| Selling, General and Administrative Expenses [Member]
Business Combination, Acquisition Related Costs				$ 40	$ 98	$ 2
Assets Acquisition of Amika Mobile Corporation [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares) \| shares		573,801	573,801							208,692
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable		$ 3,431
Business Combination, Acquisition Related Costs										$ 264
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (Year)		7 years	7 years
Asset Acquisition, Holdback Liability Deposited			$ 1
Asset Acquisition, Adjustments from Purchase Holdback Liability, Period (Year)		3 years	3 years
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares, Each Anniversaries (in shares) \| shares		191,267	191,267
Assets Acquisition of Amika Mobile Corporation [Member] \| Former Owner of Amika Mobile [Member]
Stock Issued During Period, Shares, Acquisitions (in shares) \| shares										365,109
Assets Acquisition of Amika Mobile Corporation [Member] \| Selling, General and Administrative Expenses [Member]
Business Combination, Acquisition Related Costs						$ 22	$ 10	$ 132	$ 100