Percentage of outstanding shares of common stock.

No definition available.

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- Definition

Percentage of voting power.

+ References

No definition available.

+ Details

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Namespace Prefix:	achv_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-3

+ Details

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- 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

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

+ Details

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- Details

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- Details

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- Details

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- Details

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Common Stock - Stock Warrants - Additional Information (Detail) - $ / shares	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Feb. 29, 2024
Class of Warrant or Right [Line Items]
Percentage of voting power	50.00%
Warrants Issued in December 2019 [Member]
Class of Warrant or Right [Line Items]
Warrants to purchase common stock	0	0
Pre Funded Warrants
Class of Warrant or Right [Line Items]
Percentage of outstanding shares of common stock	50.00%
Pre Funded Warrants \| Private Placement [Member]
Class of Warrant or Right [Line Items]
Exercise price per share of warrant			$ 0.001
Pre Funded Warrants \| Common Stock [Member] \| Private Placement [Member]
Class of Warrant or Right [Line Items]
Warrants to purchase common stock			13,086,151
Exercise price per share of warrant			$ 4.906