Estimated cash saving on remaining lease term due to termination of lease.

No definition available.

Name:	astc_EstimatedCashSavingOnRemainingLeaseTermDueToTerminationOfLease
Namespace Prefix:	astc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Lease contract termination costs.

+ References

No definition available.

+ Details

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Namespace Prefix:	astc_
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Balance Type:	debit
Period Type:	duration

- Definition

Lease termination impact on income statement.

+ References

No definition available.

+ Details

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Namespace Prefix:	astc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Write off of net leasehold improvement assets.

+ References

No definition available.

+ Details

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Namespace Prefix:	astc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Write off of net operating ROU asset and liability.

+ References

No definition available.

+ Details

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Namespace Prefix:	astc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

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

- Definition

The amount of an asset, typically cash, provided to a counterparty to provide certain assurance of performance by the entity pursuant to the terms of a written or oral agreement, such as a lease.

+ 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
-Subparagraph (SX 210.5-02.8,17)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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

- 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

No definition available.

+ Details

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- Details

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Namespace Prefix:
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- Details

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- Details

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- Details

Name:	srt_StatementGeographicalAxis=astc_AustinTexasMember
Namespace Prefix:
Data Type:	na
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Subsequent Events - Additional Information (Details) - USD ($) $ in Thousands	Aug. 11, 2020	Feb. 13, 2020	Sep. 05, 2019
Secured Promissory Note \| Private Placement
Subsequent Event [Line Items]
Secured note principal amount		$ 1,000	$ 1,500
Subsequent Event \| Austin, Texas
Subsequent Event [Line Items]
Impact to consolidated statements of operations in connection with lease termination	$ 552
Write off of net leasehold improvement assets	237
Write off of net operating ROU asset and liability	33
Contract termination costs	350
Security deposit	72
Estimated cash saving on remaining lease term due to termination of lease	$ 1,200