Represents the number of basis points or adjustment added to variable interest rate.

No definition available.

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

- 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

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

+ References

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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
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-Section 45
-Paragraph 12
-Subparagraph (c)
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+ Details

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

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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- Details

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- Details

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- Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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Subsequent Events (Details) - USD ($)		12 Months Ended
Subsequent Events (Details) - USD ($)	Nov. 20, 2023	Sep. 30, 2023	Sep. 30, 2022	Dec. 19, 2023	Jun. 28, 2023	May 11, 2023
Subsequent Event
Proceeds from assets held for sale			$ 2,750,576
Senior secured term loan
Subsequent Event
Aggregate principal amount					$ 20,000,000.0
Adjustment to variable interest rate		0.10%
Senior secured revolving line of credit
Subsequent Event
Aggregate principal amount						$ 10,000,000
Senior secured revolving line of credit \| SOFR
Subsequent Event
Adjustment to variable interest rate		0.10%
PNC Bank \| Senior secured term loan
Subsequent Event
Aggregate principal amount					$ 20,000,000
Minimum [Member] \| Senior secured term loan \| SOFR
Subsequent Event
Applicable Margin		1.50%
Minimum [Member] \| Senior secured revolving line of credit \| SOFR
Subsequent Event
Applicable Margin		1.50%
Maximum [Member] \| Senior secured term loan \| SOFR
Subsequent Event
Applicable Margin		2.50%
Maximum [Member] \| Senior secured revolving line of credit \| SOFR
Subsequent Event
Applicable Margin		2.50%
Subsequent Event \| Corporate aircraft
Subsequent Event
Proceeds from assets held for sale	$ 2,300,000
Subsequent Event \| Minimum [Member] \| PNC Bank \| Senior secured revolving line of credit
Subsequent Event
Aggregate principal amount				$ 10,000,000
Subsequent Event \| Maximum [Member] \| PNC Bank \| Senior secured revolving line of credit
Subsequent Event
Aggregate principal amount				$ 30,000,000