Derivative Financial Instruments (Details) (Derivative instrument liability, Warrants, USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Black-Scholes option pricing model
Range of assumptions used to determine the fair value of the warrants
Fair value of Synergy common stock (in dollars per share)	$ 6.07	$ 4.05
Expected volatility (as a percent)	60.00%	60.00%
Black-Scholes option pricing model | Minimum
Range of assumptions used to determine the fair value of the warrants
Expected warrant term	5 years	5 years
Risk-free interest rate (as a percent)	0.31%	0.51%
Black-Scholes option pricing model | Maximum
Range of assumptions used to determine the fair value of the warrants
Expected warrant term	7 years	7 years
Risk-free interest rate (as a percent)	0.77%	1.33%
Binomial model
Range of assumptions used to determine the fair value of the warrants
Fair value of Synergy common stock (in dollars per share)	$ 6.07	$ 3.28
Expected warrant term	3 years 7 months 17 days	4 years 7 months 17 days
Risk-free interest rate (as a percent)	0.36%	1.04%
Expected volatility (as a percent)	60.00%	60.00%
Dividend yield (as a percent)	0.00%	0.00%