Fair Value Measurements - Assumptions (Details)
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Lender Warrants    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Risk-free interest rate 1.97%  
Expected term 9 years 4 months 2 days  
Expected volatility 58.00%  
Dividend yield 0.00% 0.00%
Lender Warrants | Minimum    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Risk-free interest rate   2.13%
Expected term   9 years 5 months 12 days
Expected volatility   57.00%
Lender Warrants | Maximum    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Risk-free interest rate   2.58%
Expected term   10 years
Expected volatility   58.00%
Stock Option Liability Awards    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Dividend yield 0.00% 0.00%
Stock Option Liability Awards | Minimum    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Risk-free interest rate 1.46% 1.61%
Expected term 4 years 8 months 27 days 4 years 10 months 6 days
Expected volatility 51.00% 56.00%
Stock Option Liability Awards | Maximum    
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]    
Risk-free interest rate 1.67% 2.00%
Expected term 6 years 11 days 6 years 29 days
Expected volatility 53.00% 58.00%