Fair Value Measurements - Valuation Technique (Details)	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Minimum
Valuation technique for assets measured and recorded at fair value
Risk-free interest rate (as a percent)	0.68%	0.37%
Volatility (as a percent)	59.60%	55.93%
Expected average term	1 year 4 months 21 days	8 months 1 day
Maximum
Valuation technique for assets measured and recorded at fair value
Risk-free interest rate (as a percent)	0.77%	1.01%
Volatility (as a percent)	60.60%	123.53%
Expected average term	2 years 3 months 15 days	3 years 3 months 18 days