Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Warrant Liabilities And Convertible Notes At Fair Value (Detail)

v3.7.0.1
Fair Value Measurements - Warrant Liabilities And Convertible Notes At Fair Value (Detail) - $ / shares
 3 Months Ended 12 Months Ended
Mar. 31, 2017
Dec. 31, 2016
Warrants Issuable [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Risk-free interest rate   1.93%
Expected dividend yield   0.00%
Expected term in years   4 years 8 months 12 days
Expected volatility   98.23%
Avenue [Member] | Convertible Debt [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Expected dividend yield 0.00%  
Expected volatility 61.70%  
Avenue [Member] | Minimum [Member] | Convertible Debt [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Risk-free interest rate 0.91%  
Expected term in years 6 months  
Avenue [Member] | Maximum [Member] | Convertible Debt [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Risk-free interest rate 1.21%  
Expected term in years 1 year 9 months  
Avenue [Member] | Warrant [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Risk-free interest rate 2.39%  
Expected dividend yield 0.00%  
Expected term in years 9 years 9 months 4 days  
Expected volatility 86.00%  
Helocyte [Member] | Convertible Debt [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Expected dividend yield 0.00%  
Expected volatility 61.70%  
Helocyte [Member] | Minimum [Member] | Convertible Debt [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Risk-free interest rate 0.91%  
Expected term in years 6 months  
Helocyte [Member] | Maximum [Member] | Convertible Debt [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Risk-free interest rate 1.189%  
Expected term in years 1 year 7 months 28 days  
Helocyte [Member] | Warrant [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Expected dividend yield 0.00%  
Expected volatility 70.00%  
Strike price $ 0.44  
Helocyte [Member] | Warrant [Member] | Minimum [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Risk-free interest rate 1.769%  
Expected term in years 4 years 3 months  
Helocyte [Member] | Warrant [Member] | Maximum [Member]    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Risk-free interest rate 1.859%  
Expected term in years 4 years 8 months 1 day