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Stock-based Compensation - Schedule of Key Assumptions Utilized in Fair Value Calculation (Details) - Stock options
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected term (years) 5 years 11 months 25 days 6 years 26 days 6 years 3 months
Expected stock price volatility (in percentage) 83.94% 74.11% 80.44%
Risk-free interest rate (in percentage) 1.43% 1.63% 1.90%
Dividend yield (in percentage) 0.00% 0.00% 0.00%