v3.23.2

Note 13 - Commitments and Contingencies (Details Textual) | Jul. 06, 2021 | Jun. 08, 2021
--- | --- | ---
Purported Shareholder v. Company - Violation of Sections 10(b) and 20(a) of the Exchange Act and SEC Rule 10b-5 [Member] |  |
Loss Contingency, Number of Defendants |  | 2
Purported Shareholder v. Company - Alleged Misstatements as the Shareholder [Member] |  |
Loss Contingency, Number of Defendants | 10 |

X
- Definition Number of defendants named in a legal action. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483076/450-20-50-4 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483076/450-20-50-9 + Details
Name: | us-gaap_LossContingencyNumberOfDefendants
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | srt_LitigationCaseAxis=acrx_PurportedShareholderVCompanyViolationOfSections10bAnd20aOfTheExchangeActAndSecRule10b5Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_LitigationCaseAxis=acrx_PurportedShareholderVCompanyAllegedMisstatementsAsTheShareholderMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |