Name:	acrx_BusinessAcquisitionPercentageOfVotingInterestsRemainingWithAcquiredEntityShareholders
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The contingent achievement benchmarks for a contingent consideration arrangement in a business combination.

No definition available.

Name:	acrx_BusinessCombinationContingentConsiderationArrangementsContingentAchievementBenchmarks
Namespace Prefix:	acrx_
Data Type:	xbrli:monetaryItemType
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Number of common shares into which each right may be converted in a business combination.

No definition available.

Name:	acrx_BusinessCombinationNumberOfCommonSharesCalledByEachRight
Namespace Prefix:	acrx_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Represents the percentage of net sales to be paid as a royalty contingent on performance standards under the Co-Promotion Agreement.

No definition available.

Name:	acrx_CopromotionAgreementPercentOfNetSalesToBePaidAsRoyaltyContingentOnPerformanceStandards
Namespace Prefix:	acrx_
Data Type:	num:percentItemType
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Period Type:	instant

Amount of expected annual savings from restructuring and related costs.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount expected to be recognized in earnings for the specified restructuring cost.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b)(1))
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-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
-Topic 420
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-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The number of positions eliminated during the period as a result of restructuring activities.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
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Period Type:	duration

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Data Type:	na
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Data Type:	na
Balance Type:
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