Leases - Schedule of Future Minimum Lease Payments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020
Leases [Abstract]
Operating Lease, Liability, Statement of Financial Position [Extensible List]	astc:OperatingAndFinanceLeaseLiabilityCurrentAndNoncurrent
Operating Leases
2021	$ 72
2022	6
2023	6
Total lease obligations	84
Less: imputed interest	4
Present value of net minimum lease obligations	80
Less: lease liabilities - current	72
Lease liabilities - non-current	8
Financing Leases
2021	6
2022	12
2023	12
2024	12
2025	8
Total lease obligations	50
Less: imputed interest	6
Present value of net minimum lease obligations	44
Less: lease liabilities - current	10
Lease liabilities - non-current	34
Total
2021	78
2022	18
2023	18
2024	12
2025	8
Total lease obligations	134
Less: imputed interest	10
Total lease liabilities	124
Less: lease liabilities - current	82	$ 339
Lease liabilities - non-current	$ 42	$ 623

Operating and finance lease liabilities.

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- Definition

Operating and finance lease liabilities payments due.

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No definition available.

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- Definition

Operating and finance lease liability current.

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No definition available.

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Operating and finance lease liability noncurrent.

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- Definition

Operating and finance lease liability payments due.

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No definition available.

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- Definition

Operating and finance lease liability payments due next twelve months.

+ References

No definition available.

+ Details

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- Definition

Operating and finance lease liability payments due year four.

+ References

No definition available.

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- Definition

Operating and finance lease liability payments due year three.

+ References

No definition available.

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- Definition

Operating and finance lease liability payments due year two.

+ References

No definition available.

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- Definition

Operating and finance lease liability payments remainder of fiscal year.

+ References

No definition available.

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- Definition

Operating and finance lease liability undiscounted excess amount.

+ References

No definition available.

+ Details

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No definition available.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918627-209977

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

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- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease.

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in remainder of current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

+ References

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- References

No definition available.

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease.

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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- Definition

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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- Definition

Indicates line item in statement of financial position that includes operating lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918631-209977

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