Debt instrument extended maturity date.

No definition available.

Name:	astc_DebtInstrumentExtendedMaturityDate
Namespace Prefix:	astc_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Cash deposited in a special reserve account for the exclusive benefit of customers pursuant to SEC Regulations.

+ References

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+ Details

Name:	us-gaap_CashReserveDepositRequiredAndMade
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

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+ Details

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

- Definition

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

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+ Details

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

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
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

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

- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

+ References

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+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

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+ Details

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

- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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+ Details

Name:	us-gaap_InterestExpenseDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from a borrowing supported by a written promise to pay an obligation.

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+ Details

Name:	us-gaap_ProceedsFromNotesPayable
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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+ Details

Name:	us-gaap_RepaymentsOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=astc_TwoThousandNineteenSecuredPromissoryNoteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DebtInstrumentAxis=astc_PaycheckProtectionProgramPromissoryNoteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TypeOfArrangementAxis=astc_CashReserveAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=astc_CommercialBankMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsidiarySaleOfStockAxis=us-gaap_PrivatePlacementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

Debt - Additional Information (Details) - USD ($) $ in Thousands					12 Months Ended
	Sep. 03, 2021	Aug. 24, 2020	Apr. 14, 2020	Sep. 05, 2019	Jun. 30, 2021	Jun. 30, 2020	Oct. 19, 2020	Feb. 13, 2020
Debt Instrument [Line Items]
Proceeds from term note payable					$ 0	$ 542
2019 Secured Promissory Note \| Subsequent Events
Debt Instrument [Line Items]
Extended maturity date	Sep. 05, 2022
Repayments of note	$ 1,000
PPP Promissory Note
Debt Instrument [Line Items]
Interest on the Note			1.00%
Maturity date			Apr. 01, 2022
Proceeds from term note payable			$ 542
Debt instrument, frequency of periodic payment			monthly
Debt instrument, payment terms			Payments are due monthly beginning November 10, 2020. The principal amount of the PPP Promissory Note along with any unpaid interest is due on April 1, 2022.
PPP Promissory Note \| Cash Reserve Agreement \| Commercial Bank
Debt Instrument [Line Items]
Cash amount held in separate account							$ 542
Private Placement
Debt Instrument [Line Items]
Interest expense on notes					$ 275	$ 177
Private Placement \| 2019 Secured Promissory Note
Debt Instrument [Line Items]
Secured note principal amount				$ 1,500
Interest on the Note				11.00%
Maturity date				Sep. 05, 2020
Extended maturity date		Sep. 05, 2021
Private Placement \| 2020 Secured Promissory Note
Debt Instrument [Line Items]
Secured note principal amount								$ 1,000
Interest on the Note								11.00%