Quarterly report pursuant to Section 13 or 15(d)

Equity - Additional Information (Details)

v2.4.1.9
Equity - Additional Information (Details) (USD $)
 3 Months Ended 0 Months Ended
Mar. 31, 2015
Nov. 26, 2014
Dec. 31, 2014
Class Of Stock [Line Items]      
Noncash exercise provision threshold 120 days    
Restricted common stock issued 30,000us-gaap_StockIssuedDuringPeriodSharesOther    
Common stock shares issued upon vesting of restricted stock units 617,447us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross    
Shares withheld 206,380us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation    
Treasury Stock $ 120,000us-gaap_TreasuryStockValue   $ 0us-gaap_TreasuryStockValue
Common Stock      
Class Of Stock [Line Items]      
Equity issuance unit   1amda_DevelopmentStageEntitiesEquityIssuanceUnit
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember 		 
Common stock shares issued upon conversion from preferred stock 242us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember 		   
Warrant      
Class Of Stock [Line Items]      
Equity issuance unit   1amda_DevelopmentStageEntitiesEquityIssuanceUnit
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_WarrantMember 		 
Volatility rate 135.00%us-gaap_FairValueAssumptionsExpectedVolatilityRate
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_WarrantMember 		   
Secondary Offering      
Class Of Stock [Line Items]      
Common stock shares, issued   11,441,646us-gaap_StockIssuedDuringPeriodSharesNewIssues
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingMember 		 
Common stock share issue price under offering, per share price   1.14us-gaap_EquityIssuancePerShareAmount
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingMember 		 
Exercise price of warrants   1.48us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingMember 		 
Secondary Offering Warrant      
Class Of Stock [Line Items]      
Warrants exercised 913,145amda_ClassofWarrantorRightWarrantsExercised
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember 		   
Class of warrant outstanding 12,244,747us-gaap_ClassOfWarrantOrRightOutstanding
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember 		   
Cash to exercise warrants $ 9,700,000us-gaap_WarrantsAndRightsOutstanding
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember 		   
Outstanding warrants exercisable 22,524,640us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember 		   
Secondary Offering Warrant | Underwriter Option      
Class Of Stock [Line Items]      
Common stock shares, issued   1,716,246us-gaap_StockIssuedDuringPeriodSharesNewIssues
/ us-gaap_CounterpartyNameAxis
= amda_UnderwriterOptionMember
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember 		 
Secondary Offering Warrant | Common Stock      
Class Of Stock [Line Items]      
Warrants converted into shares of common stock 1,717,840amda_StockIssuedDuringPeriodSharesWarrantsExercised
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember