Assets Held for Sale - Classifications (Details) - USD ($)	Sep. 30, 2024	Sep. 30, 2023
Long-Lived Assets Held-for-Sale [Line Items]
Less: accumulated depreciation and amortization		$ (342,650)
Assets held for sale	$ 0	2,063,818
Corporate aircraft
Long-Lived Assets Held-for-Sale [Line Items]
Assets held for sale, gross		$ 2,406,468

Amount of accumulated depreciation, depletion and amortization of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

No definition available.

+ Details

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Namespace Prefix:	issc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of gross assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

+ References

No definition available.

+ Details

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

- Definition

Amount of assets held-for-sale that are not part of a disposal group, expected to be sold within a year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481372/852-10-55-10

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 360
-SubTopic 10
-Name Accounting Standards Codification
-Section 15
-Paragraph 4
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482309/360-10-15-4

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
Period Type:	instant

- 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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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