Annual report pursuant to Section 13 and 15(d)

Fair Value Measurements (Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details)

v2.4.1.9
Fair Value Measurements (Schedule Of Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) (USD $)
Dec. 31, 2014
Dec. 31, 2013
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Assets: $ 22,872,051us-gaap_AssetsFairValueDisclosure $ 296,130us-gaap_AssetsFairValueDisclosure
Warrant Liabilities 3,768,351us-gaap_LiabilitiesFairValueDisclosure 5,034,058us-gaap_LiabilitiesFairValueDisclosure
Corporate Bonds [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Assets: 2,035,870us-gaap_AssetsFairValueDisclosure
/ us-gaap_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesByTypeAxis
= us-gaap_CorporateBondSecuritiesMember
 
State and Municipal Obligations [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Assets:   100,000us-gaap_AssetsFairValueDisclosure
/ us-gaap_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesByTypeAxis
= us-gaap_USStatesAndPoliticalSubdivisionsMember
Restricted Cash Equivalents [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Assets:   196,130us-gaap_AssetsFairValueDisclosure
/ us-gaap_CashAndCashEquivalentsAxis
= rnn_RestrictedCashEquivalentsMember
Certificates of Deposit [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Assets: 18,838,271us-gaap_AssetsFairValueDisclosure
/ us-gaap_CashAndCashEquivalentsAxis
= us-gaap_CertificatesOfDepositMember
 
Commercial Paper [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Assets: 1,997,910us-gaap_AssetsFairValueDisclosure
/ us-gaap_CashAndCashEquivalentsAxis
= us-gaap_CommercialPaperNotIncludedWithCashAndCashEquivalentsMember
 
Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Assets:   258,630us-gaap_AssetsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
Level 1 [Member] | State and Municipal Obligations [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Assets:   100,000us-gaap_AssetsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesByTypeAxis
= us-gaap_USStatesAndPoliticalSubdivisionsMember
Level 1 [Member] | Restricted Cash Equivalents [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Assets:   158,630us-gaap_AssetsFairValueDisclosure
/ us-gaap_CashAndCashEquivalentsAxis
= rnn_RestrictedCashEquivalentsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
Level 2 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Assets: 22,872,051us-gaap_AssetsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
37,500us-gaap_AssetsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
Level 2 [Member] | Corporate Bonds [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Assets: 2,035,870us-gaap_AssetsFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
/ us-gaap_SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesByTypeAxis
= us-gaap_CorporateBondSecuritiesMember
 
Level 2 [Member] | Restricted Cash Equivalents [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Assets:   37,500us-gaap_AssetsFairValueDisclosure
/ us-gaap_CashAndCashEquivalentsAxis
= rnn_RestrictedCashEquivalentsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
Level 2 [Member] | Certificates of Deposit [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Assets: 18,838,271us-gaap_AssetsFairValueDisclosure
/ us-gaap_CashAndCashEquivalentsAxis
= us-gaap_CertificatesOfDepositMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
 
Level 2 [Member] | Commercial Paper [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Total Assets: 1,997,910us-gaap_AssetsFairValueDisclosure
/ us-gaap_CashAndCashEquivalentsAxis
= us-gaap_CommercialPaperNotIncludedWithCashAndCashEquivalentsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel2Member
 
Level 3 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Warrant Liabilities $ 3,768,351us-gaap_LiabilitiesFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
$ 5,034,058us-gaap_LiabilitiesFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member