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

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section 50
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+ Details

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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

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

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-Name Accounting Standards Codification
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-SubTopic 10
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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:	num: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 CCYY-MM-DD format.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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+ Details

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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.

+ References

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Balance Type:	na
Period Type:	duration

- Definition

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

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+ Details

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

- Definition

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

+ References

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+ Details

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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

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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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Balance Type:
Period Type:

- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

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Debt - Additional Information (Details) - USD ($) $ in Thousands				3 Months Ended	9 Months Ended
	Aug. 24, 2020	Apr. 14, 2020	Sep. 05, 2019	Mar. 31, 2021	Mar. 31, 2021	Oct. 19, 2020	Feb. 13, 2020
Private Placement
Debt Instrument [Line Items]
Interest expense on both notes				$ 68	$ 206
Secured Promissory Note \| Private Placement
Debt Instrument [Line Items]
Secured note principal amount			$ 1,500				$ 1,000
Interest on the Note			11.00%				11.00%
Maturity date			Sep. 05, 2020
Extended maturity date	Sep. 05, 2021
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 remaining principal amount of the PPP Promissory Note along with any unpaid interest is due on April 1, 2022.
Interest expense				$ 1	$ 2
PPP Promissory Note \| Cash Reserve Agreement \| Commercial Bank
Debt Instrument [Line Items]
Cash amount held in separate account						$ 542