XML 44 R41.htm IDEA: XBRL DOCUMENT
v3.20.1

Subsequent Events - Additional Information (Detail) - Subsequent Event [Member] - Private Placement [Member] - USD ($) $ / shares in Units, $ in Millions | Apr. 28, 2020 | Apr. 27, 2020
--- | --- | ---
Subsequent Event [Line Items] |  |
Common stock, shares issued | 5,615,653 |
Common stock, price per share | $ 0.33 |
Warrants to purchase shares of common stock | 0.75 |
Description of stock units issued | each unit consisting of one share of common stock and a warrant to purchase 0.75 shares of common stock |
Exercise price per unit of warrant | $ 0.366 | $ 0.362
Warrant exercisable date | Oct. 27, 2020 |
Warrant expiration date | Apr. 27, 2025 |
Gross proceeds from issuance of common stock | $ 1.9 |
Placement agent fees and offering expenses | 0.3 |
Proceeds from issuance of common stock | $ 1.6 |
Placement Agent [Member] |  |
Subsequent Event [Line Items] |  |
Exercise price per unit of warrant | $ 0.3795 |
Maximum number of common shares issuable per warrant upon conversion | 505,409 |

X
- Definition Gross proceeds from issuance of common stock. + References No definition available. + Details
Name: | achv_GrossProceedsFromIssuanceOfCommonStock
Namespace Prefix: | achv_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Maximum number of common shares issuable per warrant upon conversion. + References No definition available. + Details
Name: | achv_MaximumNumberOfCommonSharesIssuablePerWarrantUponConversion
Namespace Prefix: | achv_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Placement agent fees and offering expenses. + References No definition available. + Details
Name: | achv_PlacementAgentFeesAndOfferingExpenses
Namespace Prefix: | achv_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Stock units description. + References No definition available. + Details
Name: | achv_StockUnitsDescription
Namespace Prefix: | achv_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Warrant expiration date. + References No definition available. + Details
Name: | achv_WarrantExpirationDate
Namespace Prefix: | achv_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Warrants to purchase shares of common stock. + References No definition available. + Details
Name: | achv_WarrantsToPurchaseSharesOfCommonStock
Namespace Prefix: | achv_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Date the warrants or rights are exercisable, in CCYY-MM-DD format. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(i)(3)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
Name: | us-gaap_ClassOfWarrantOrRighstDateFromWhichWarrantsOrRightsExercisable
Namespace Prefix: | us-gaap_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Exercise price per share or per unit of warrants or rights outstanding. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(i)(4)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 + Details
Name: | us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition The cash inflow from the additional capital contribution to the entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585 + Details
Name: | us-gaap_ProceedsFromIssuanceOfCommonStock
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Per share or per unit amount of equity securities issued. + References No definition available. + Details
Name: | us-gaap_SharesIssuedPricePerShare
Namespace Prefix: | us-gaap_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of new stock issued during the period. + 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(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 4: 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(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- 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
Name: | us-gaap_SubsequentEventLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsidiarySaleOfStockAxis=us-gaap_PrivatePlacementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_TitleOfIndividualAxis=achv_PlacementAgentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |