Range of Exercise Price 0.00-40.00 [Member]Options Outstanding, Range of Exercise Price Lower $ 0.00Options Outstanding, Range of Exercise Price Upper $ 40.00Options Outstanding, Options | shares 2,431,708Options Outstanding, Weighted Average Exercise Price $ 1.38Options Outstanding, Weighted Average Remaining Contractual Life 6 years 6 months 29 daysOptions Exercisable, Options | shares 288,645Options Exercisable, Weighted Average Exercise Price $ 7.56Options Exercisable, Weighted Average Remaining Contractual Life 5 years 5 months 16 daysRange of Exercise Price 41.00-70.00 [Member]Options Outstanding, Range of Exercise Price Lower $ 41.00Options Outstanding, Range of Exercise Price Upper $ 70.00Options Outstanding, Options | shares 8,364Options Outstanding, Weighted Average Exercise Price $ 50.29Options Outstanding, Weighted Average Remaining Contractual Life 3 years 7 months 6 daysOptions Exercisable, Options | shares 8,364Options Exercisable, Weighted Average Exercise Price $ 50.29Options Exercisable, Weighted Average Remaining Contractual Life 3 years 7 months 6 daysRange Of Exercise Price 71.09-102.00 [Member]Options Outstanding, Range of Exercise Price Lower $ 71.00Options Outstanding, Range of Exercise Price Upper $ 102.00Options Outstanding, Options | shares 61,940Options Outstanding, Weighted Average Exercise Price $ 85.02Options Outstanding, Weighted Average Remaining Contractual Life 4 years 26 daysOptions Exercisable, Options | shares 61,940Options Exercisable, Weighted Average Exercise Price $ 85.02Options Exercisable, Weighted Average Remaining Contractual Life 4 years 26 daysName: us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=syn_RangeOfExercisePrice0004000MemberName: us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=syn_RangeOfExercisePrice41007000MemberName: us-gaap_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansByExercisePriceRangeAxis=syn_RangeOfExercisePrice710010200Member
