v3.23.2

Note 11 - Liability Related to Sale of Future Royalties (Details Textual) - USD ($) $ in Thousands |  |  | 1 Months Ended | 12 Months Ended | 87 Months Ended
--- | --- | --- | --- | --- | ---
May 31, 2022 | Sep. 18, 2015 | Sep. 30, 2015 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2022
Proceeds From Sale of Royalty and Milestone Rights |  | $ 65,000 | $ 65,000 |  |  |
Consideration Paid for Termination of Royalty Monetization | $ 100 |  |  | $ 100 |  | $ 100
Non-cash Gain on Termination of Liability Related to Sale of Future Royalties | $ 84,100 |  |  | $ 84,152 | $ (0) |
Effective Annual Interest Rate |  |  |  | 3.20% | 3.50% |
SWK [Member] |  |  |  |  |  |
Percentage of Royalties and Rights Under Agreement |  | 75.00% |  |  |  |
SWK [Member] | First Four Commercial Milestones [Member] |  |  |  |  |  |
Percentage of Royalties and Rights Under Agreement |  | 80.00% |  |  |  |
Commercial Milestones Value Maximum Amount Available |  | $ 35,600 |  |  |  |
AcelRX [Member] | First Four Commercial Milestones [Member] |  |  |  |  |  |
Commercial Milestones Value Maximum Amount Available |  | $ 44,500 |  |  |  |

X
- Definition The maximum value of commercial milestone payments available to the company. + References No definition available. + Details
Name: | acrx_CommercialMilestonesValueMaximumAmountAvailable
Namespace Prefix: | acrx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of consideration paid for termination of Royalty Monetization. + References No definition available. + Details
Name: | acrx_ConsiderationPaidForTerminationOfRoyaltyMonetization
Namespace Prefix: | acrx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Effective annual rate for a liability related to sale of future royalties. + References No definition available. + Details
Name: | acrx_EffectiveAnnualInterestRate
Namespace Prefix: | acrx_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of non-cash gain on termination of liability related to sale of future royalties. + References No definition available. + Details
Name: | acrx_NonCashGainOnTerminationOfLiabilityRelatedToSaleOfFutureRoyalties
Namespace Prefix: | acrx_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Percentage of royalties or milestone rights to be received under the agreement. + References No definition available. + Details
Name: | acrx_PercentageOfRoyaltiesAndRightsUnderAgreement
Namespace Prefix: | acrx_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of proceeds from the sale of royalty and milestone rights. + References No definition available. + Details
Name: | acrx_ProceedsFromSaleOfRoyaltyAndMilestoneRights
Namespace Prefix: | acrx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=acrx_SWKMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TypeOfArrangementAxis=acrx_FirstFourCommercialMilestonesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=acrx_AcelRXMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |