Annual report pursuant to Section 13 and 15(d)

Warrants (Narrative) (Details)

v2.4.1.9
Warrants (Narrative) (Details) (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Class of Warrant or Right [Line Items]      
Number of warrants, Outstanding 13,205,871us-gaap_ClassOfWarrantOrRightOutstanding 24,968,868us-gaap_ClassOfWarrantOrRightOutstanding 21,656,142us-gaap_ClassOfWarrantOrRightOutstanding
Exercise price $ 1.07invest_InvestmentWarrantsExercisePrice $ 0.86invest_InvestmentWarrantsExercisePrice $ 0.89invest_InvestmentWarrantsExercisePrice
Warrant expiration date, start Jul. 05, 2016    
Warrant expiration date, end Jan. 21, 2019    
Average remaining contractual life of warrants outstanding 3 years 2 months 12 days 3 years 2 months 12 days  
Probability of entering into a fundamental transaction 5.00%rnn_ProbabilityOfEnteringIntoFundamentalTransaction    
Maximum [Member]      
Class of Warrant or Right [Line Items]      
Exercise price $ 1.50invest_InvestmentWarrantsExercisePrice
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
   
Minimum [Member]      
Class of Warrant or Right [Line Items]      
Exercise price $ 0.41invest_InvestmentWarrantsExercisePrice
/ us-gaap_RangeAxis
= us-gaap_MinimumMember