Note 11 - Supplemental Cash Flow Disclosure - Changes in Working Capital Items (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Supplemental Cash Flow Elements [Abstract]
Receivables	$ (434)	$ 93
Prepaid expenses	(839)	(653)
Trade and other payables	2	27
Increase (Decrease) in Non-cash Working Capital	$ (1,271)	$ (533)

Increase decrease in non-cash working capital.

No definition available.

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Namespace Prefix:	acst_
Data Type:	xbrli:monetaryItemType
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- Definition

The increase (decrease) during the reporting period in the amounts payable to vendors for goods and services received and the amount of obligations and expenses incurred but not paid.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3602-108585

+ Details

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

- Definition

The increase (decrease) during the reporting period in the amount of outstanding money paid in advance for goods or services that bring economic benefits for future periods.

+ References

+ Details

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

- Definition

The increase (decrease) during the reporting period in the total amount due within one year (or one operating cycle) from all parties, associated with underlying transactions that are classified as operating activities.

+ References

+ Details

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Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

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Balance Type:	na
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