Quarterly report pursuant to Section 13 or 15(d)

Warrants (Summary Of Shares Indexed To The Warrants) (Details)

v2.4.1.9
Warrants (Summary Of Shares Indexed To The Warrants) (Details)
Mar. 31, 2015
Dec. 31, 2014
Class of Warrant or Right [Line Items]    
Number of shares indexed 13,205,871rnn_InvestmentWarrantsNumberOfSharesIndexed 13,205,871rnn_InvestmentWarrantsNumberOfSharesIndexed
March 31, 2011 Warrants To Institutional Investors [Member]    
Class of Warrant or Right [Line Items]    
Number of shares indexed 3,333,333rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateEWarrantsToInstitutionalInvestorsMember 		3,333,333rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateEWarrantsToInstitutionalInvestorsMember
December 4, 2012 Warrants To Institutional Investors [Member]    
Class of Warrant or Right [Line Items]    
Number of shares indexed 221,600rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateFWarrantsToInstitutionalInvestorsMember 		221,600rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateFWarrantsToInstitutionalInvestorsMember
December 4, 2012 Warrants To Placement Agent [Member]    
Class of Warrant or Right [Line Items]    
Number of shares indexed 40,000rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateFWarrantsToPlacementAgentMember 		40,000rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateFWarrantsToPlacementAgentMember
July 26, 2013 Warrants To Institutional Investors [Member]    
Class of Warrant or Right [Line Items]    
Number of shares indexed 2,000,000rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateGWarrantsToInstitutionalInvestorsMember 		2,000,000rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateGWarrantsToInstitutionalInvestorsMember
July 26, 2013 Warrants To Placement Agent [Member]    
Class of Warrant or Right [Line Items]    
Number of shares indexed 124,032rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateGWarrantsToPlacementAgentMember 		124,032rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateGWarrantsToPlacementAgentMember
October 16, 2013 Warrants To Institutional Investors [Member]    
Class of Warrant or Right [Line Items]    
Number of shares indexed 2,317,309rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateHWarrantsToInstitutionalInvestorsMember 		2,317,309rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateHWarrantsToInstitutionalInvestorsMember
October 16, 2013 Warrants To Placement Agent [Member]    
Class of Warrant or Right [Line Items]    
Number of shares indexed 407,692rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateHWarrantsToPlacementAgentMember 		407,692rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateHWarrantsToPlacementAgentMember
January 21, 2014 Warrants To Institutional Investors [Member]    
Class of Warrant or Right [Line Items]    
Number of shares indexed 4,761,905rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateIWarrantsToInstitutionalInvestorsMember 		4,761,905rnn_InvestmentWarrantsNumberOfSharesIndexed
/ us-gaap_ClassOfWarrantOrRightAxis
= rnn_DateIWarrantsToInstitutionalInvestorsMember