v3.8.0.1

Note 8 - Liability Related to Sale of Future Royalties (Details Textual) - USD ($) $ in Thousands |  | 1 Months Ended | 3 Months Ended
--- | --- | --- | ---
Sep. 18, 2015 | Sep. 30, 2015 | Dec. 31, 2017
Proceeds From Sale of Royalty and Milestone Rights | $ 65,000 | $ 65,000 |
Royalty Arrangment Maximum Payments | $ 195,000 | 195,000 |
Revenue Recognition Milestone Method Agreed, Additional Amount |  | $ 15,000 |
Effective Annual Interest Rate | 14.00% | 14.00% |
Royalty Revenue |  |  | $ 31
First Four Commercial Milestones [Member] |  |  |
Percentage of Royalties and Rights Under Agreement | 20.00% |  |
Royalties [Member] |  |  |
Percentage of Royalties and Rights Under Agreement | 25.00% |  |
Remaining Commercial and All Development Milestone[Member] |  |  |
Percentage of Royalties and Rights Under Agreement | 100.00% |  |
Commercial Milestones Value | $ 43,500 |  |
MAA Aproval [Member] |  |  |
Revenue Recognition Milestone Method Agreed, Additional Amount | 15,000 |  |
PDL [Member] |  |  |
Proceeds From Sale of Royalty and Milestone Rights | $ 61,200 |  |
Percentage of Royalties and Rights Under Agreement | 75.00% |  |
PDL [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 value of commercial milestone payments. + References No definition available. + Details
Name: | acrx_CommercialMilestonesValue
Namespace Prefix: | acrx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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 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: | num:percentItemType
Balance Type: | na
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: | num: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
- Definition Represents the agreed additional amount of revenue recognition for the milestone method. + References No definition available. + Details
Name: | acrx_RevenueRecognitionMilestoneMethodAgreedAdditionalAmount
Namespace Prefix: | acrx_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The capped amount of payments of company required to make to PDL. + References No definition available. + Details
Name: | acrx_RoyaltyArrangmentMaximumPayments
Namespace Prefix: | acrx_
Data Type: | xbrli:monetaryItemType
Balance Type: | na
Period Type: | duration

X
- Definition Revenue earned during the period from the leasing or otherwise lending to a third party the entity's rights or title to certain property. Royalty revenue is derived from a percentage or stated amount of sales proceeds or revenue generated by the third party using the entity's property. Examples of property from which royalties may be derived include patents and oil and mineral rights. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(e)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
Name: | us-gaap_RoyaltyRevenue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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

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

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

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

X
- Details
Name: | dei_LegalEntityAxis=acrx_PDLMember
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: |