Annual report pursuant to Section 13 and 15(d)

Equity - Additional Information (Details)

v2.4.1.9
Equity - Additional Information (Details) (USD $)
12 Months Ended 0 Months Ended 1 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Feb. 12, 2014
Nov. 26, 2014
Feb. 28, 2014
Sep. 30, 2013
Aug. 31, 2013
Class Of Stock [Line Items]              
Common stock, authorized 250,000,000us-gaap_CommonStockSharesAuthorized 250,000,000us-gaap_CommonStockSharesAuthorized          
Convertible preferred stock, authorized 130,000,000us-gaap_TemporaryEquitySharesAuthorized 100,000,000us-gaap_TemporaryEquitySharesAuthorized          
Common stock shares, issued 50,583us-gaap_StockIssuedDuringPeriodSharesNewIssues            
Proceeds from issuance of common stock, net of issuance costs $ 15,369,000us-gaap_ProceedsFromIssuanceOfCommonStock            
Maximum denominator to calculate conversion ratio 8.00amda_MaximumDenominatorToCalculateConversionRatio            
Preferred stock converted to common, Value 162,432,000us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities            
Proceeds from issuance of units, net of issuance costs 11,320,000amda_ProceedsFromIssuanceOfUnits            
Additional paid-in capital / (capital deficiency) 179,148,000us-gaap_AdditionalPaidInCapitalCommonStock (13,144,000)us-gaap_AdditionalPaidInCapitalCommonStock          
Restricted common stock issued, Shares, Termination of consulting agreement 50,000us-gaap_StockIssuedDuringPeriodSharesIssuedForServices            
Common stock shares issued upon vesting of restricted stock units 444,403us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardGross            
Issuance of common stock in connection with exercise of warrants, Shares 9,328amda_IssuanceOfCommonStockUponExerciseOfWarrantsShares            
Convertible preferred stock, issued 0us-gaap_TemporaryEquitySharesIssued 80,910,394us-gaap_TemporaryEquitySharesIssued          
Convertible preferred stock, par value $ 0.01us-gaap_TemporaryEquityParOrStatedValuePerShare $ 0.01us-gaap_TemporaryEquityParOrStatedValuePerShare          
Convertible preferred stock, outstanding 0us-gaap_TemporaryEquitySharesOutstanding 80,910,394us-gaap_TemporaryEquitySharesOutstanding          
Dividend declared value 0us-gaap_Dividends 0us-gaap_Dividends          
Preferred stock voting rights Unless an affirmative vote of 50% of the combined outstanding shares of preferred stock, voting separately as a class, is obtained, the Company shall not undertake any of the following: (i) declaration or payment of any dividend or other distribution or payment on the (or the redemption, purchase or other acquisition for value of any) capital stock of the Company or any subsidiary; (ii) any liquidation, dissolution, recapitalization or reorganization of the Company; (iii) transfer or disposition of assets or rights with a value of more than $1,000,000; and/or (iv) any amendment to the Company’s certificate of incorporation that changes or alters any of the preferences, voting powers or other rights and privileges of preferred stock.            
Percentage of affirmative vote by shareholders 50.00%amda_PercentageOfAffirmativeVoteByShareholders            
Assets transferred to held for disposition 1,000,000amda_AssetsTransferredToHeldForDispositionDuringPeriod            
Registration rights descriptions The preferred stockholders and warrant holders were granted registration rights that provide these holders the right to request, beginning 180 days after the completion of a qualifying initial public offering, that the Company file a registration statement to register under the Securities Act the common stock that would be issued upon conversion of the preferred shares or exercise of the warrants.            
Registration rights period 180 days            
IPO              
Class Of Stock [Line Items]              
Common stock shares, issued     3,682,900us-gaap_StockIssuedDuringPeriodSharesNewIssues
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_IPOMember
       
Preferred stock, par value     $ 5.75us-gaap_EquityIssuancePerShareAmount
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_IPOMember
       
Proceeds from issuance of common stock, net of issuance costs     15,400,000us-gaap_ProceedsFromIssuanceOfCommonStock
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_IPOMember
       
Underwriting discounts and other offering costs     5,800,000us-gaap_ExpenseRelatedToDistributionOrServicingAndUnderwritingFees
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_IPOMember
       
IPO | Underwriter Option              
Class Of Stock [Line Items]              
Common stock shares, issued     182,900us-gaap_StockIssuedDuringPeriodSharesNewIssues
/ us-gaap_CounterpartyNameAxis
= amda_UnderwriterOptionMember
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_IPOMember
       
Secondary Offering Warrant              
Class Of Stock [Line Items]              
Common stock shares, issued 15,479,873us-gaap_StockIssuedDuringPeriodSharesNewIssues
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
           
Underwriting discounts and other offering costs       1,700,000us-gaap_ExpenseRelatedToDistributionOrServicingAndUnderwritingFees
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
     
Common stock share issue price under secondary offering, per share price       $ 1.14us-gaap_SaleOfStockPricePerShare
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
     
Proceeds from issuance of units, net of issuance costs       11,300,000amda_ProceedsFromIssuanceOfUnits
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
     
Class of warrant or right on over allotment option       1,716,246amda_ClassOfWarrantOrRightOnOverAllotmentOption
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
     
Common shares exercise price $ 1.48amda_CommonSharesExercisePrice
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
           
Secondary offering warrants termination date Nov. 26, 2019            
Lieu of payment of the exercise provision days 120 days            
Expected volatility rate 135.00%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRateMaximum
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
           
Expected remaining term warrant 5 years            
Estimated fair value of the secondary offering warrants       10,500,000us-gaap_FairValueAdjustmentOfWarrants
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
     
Gross derivative liabilities       13,000,000amda_ProceedsFromIssuanceOfUnitsGross
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
     
Proceeds from issuance of equity       2,500,000us-gaap_ProceedsFromIssuanceOrSaleOfEquity
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
     
Offering costs expensed       2,000,000amda_OfferingCosts
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
     
Additional paid-in capital / (capital deficiency) 488,000us-gaap_AdditionalPaidInCapitalCommonStock
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
           
Unit Option, unit exercise price $ 1.43amda_UnitExercisePrice
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
           
Unit Option determined to be liability, estimated fair value 658,000amda_UnitClassifiedAsLiabilityFairValueDisclosure
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
           
Secondary Offering Warrant | Minimum              
Class Of Stock [Line Items]              
Percentage of common stock exceeds exercise price 25.00%amda_PercentageOfCommonStockExceedsExercisePrice
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
           
Number of consecutive trading day 20 days            
Convertible Preferred Stock              
Class Of Stock [Line Items]              
Convertible preferred stock, authorized 130,000,000us-gaap_TemporaryEquitySharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= us-gaap_ConvertiblePreferredStockMember
100,000,000us-gaap_TemporaryEquitySharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= us-gaap_ConvertiblePreferredStockMember
         
Preferred stock converted to common, Value (161,456,000)us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities
/ us-gaap_StatementClassOfStockAxis
= us-gaap_ConvertiblePreferredStockMember
           
Convertible preferred stock, outstanding 0us-gaap_TemporaryEquitySharesOutstanding
/ us-gaap_StatementClassOfStockAxis
= us-gaap_ConvertiblePreferredStockMember
           
Convertible Preferred Stock | IPO              
Class Of Stock [Line Items]              
Common stock shares issued upon conversion from preferred stock (80,910,394)us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities
/ us-gaap_StatementClassOfStockAxis
= us-gaap_ConvertiblePreferredStockMember
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_IPOMember
      80,910,394us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities
/ us-gaap_StatementClassOfStockAxis
= us-gaap_ConvertiblePreferredStockMember
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_IPOMember
   
Preferred stock converted to common, Value         161,500,000us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities
/ us-gaap_StatementClassOfStockAxis
= us-gaap_ConvertiblePreferredStockMember
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_IPOMember
   
Series F Warrants [Member] | IPO              
Class Of Stock [Line Items]              
Number of preferred stock converted to common shares         67,499us-gaap_ConversionOfStockSharesConverted1
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFWarrantsMember
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_IPOMember
   
Series F Convertible Preferred Stock              
Class Of Stock [Line Items]              
Convertible preferred stock, authorized   20,710,000us-gaap_TemporaryEquitySharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
         
Number of preferred stock converted to common shares         19,627,500us-gaap_ConversionOfStockSharesConverted1
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
   
Convertible preferred stock, issued   19,627,500us-gaap_TemporaryEquitySharesIssued
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
      4,740,000us-gaap_TemporaryEquitySharesIssued
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
4,740,000us-gaap_TemporaryEquitySharesIssued
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
Convertible preferred stock, par value           2.00us-gaap_TemporaryEquityParOrStatedValuePerShare
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
2.00us-gaap_TemporaryEquityParOrStatedValuePerShare
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
Convertible preferred stock, outstanding   19,627,500us-gaap_TemporaryEquitySharesOutstanding
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
         
Convertible preferred stock liquidation preference shares $ 2.00us-gaap_TemporaryEquityLiquidationPreferencePerShare
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
           
Series A Convertible Preferred Stock              
Class Of Stock [Line Items]              
Convertible preferred stock, authorized   5,800,000us-gaap_TemporaryEquitySharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesAConvertiblePreferredStockMember
         
Convertible preferred stock, issued   5,365,398us-gaap_TemporaryEquitySharesIssued
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesAConvertiblePreferredStockMember
         
Convertible preferred stock, outstanding   5,365,398us-gaap_TemporaryEquitySharesOutstanding
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesAConvertiblePreferredStockMember
         
Convertible preferred stock liquidation preference shares $ 0.60us-gaap_TemporaryEquityLiquidationPreferencePerShare
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesAConvertiblePreferredStockMember
           
Series A One Convertible Preferred Stock              
Class Of Stock [Line Items]              
Convertible preferred stock, authorized   10,400,000us-gaap_TemporaryEquitySharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesAOneConvertiblePreferredStockMember
         
Convertible preferred stock, issued   10,390,463us-gaap_TemporaryEquitySharesIssued
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesAOneConvertiblePreferredStockMember
         
Convertible preferred stock, outstanding   10,390,463us-gaap_TemporaryEquitySharesOutstanding
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesAOneConvertiblePreferredStockMember
         
Convertible preferred stock liquidation preference shares $ 0.60us-gaap_TemporaryEquityLiquidationPreferencePerShare
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesAOneConvertiblePreferredStockMember
           
Series B Convertible Preferred Stock              
Class Of Stock [Line Items]              
Convertible preferred stock, authorized   2,300,000us-gaap_TemporaryEquitySharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesBConvertiblePreferredStockMember
         
Convertible preferred stock, issued   1,944,147us-gaap_TemporaryEquitySharesIssued
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesBConvertiblePreferredStockMember
         
Convertible preferred stock, outstanding   1,944,147us-gaap_TemporaryEquitySharesOutstanding
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesBConvertiblePreferredStockMember
         
Convertible preferred stock liquidation preference shares $ 1.20us-gaap_TemporaryEquityLiquidationPreferencePerShare
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesBConvertiblePreferredStockMember
           
Series B One Convertible Preferred Stock              
Class Of Stock [Line Items]              
Convertible preferred stock, authorized   3,300,000us-gaap_TemporaryEquitySharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesBOneConvertiblePreferredStockMember
         
Convertible preferred stock, issued   3,299,141us-gaap_TemporaryEquitySharesIssued
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesBOneConvertiblePreferredStockMember
         
Convertible preferred stock, outstanding   3,299,141us-gaap_TemporaryEquitySharesOutstanding
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesBOneConvertiblePreferredStockMember
         
Convertible preferred stock liquidation preference shares $ 1.20us-gaap_TemporaryEquityLiquidationPreferencePerShare
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesBOneConvertiblePreferredStockMember
           
Series C Convertible Preferred Stock              
Class Of Stock [Line Items]              
Convertible preferred stock, authorized   7,900,000us-gaap_TemporaryEquitySharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesCConvertiblePreferredStockMember
         
Convertible preferred stock, issued   6,682,562us-gaap_TemporaryEquitySharesIssued
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesCConvertiblePreferredStockMember
         
Convertible preferred stock, outstanding   6,682,562us-gaap_TemporaryEquitySharesOutstanding
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesCConvertiblePreferredStockMember
         
Convertible preferred stock liquidation preference shares $ 2.00us-gaap_TemporaryEquityLiquidationPreferencePerShare
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesCConvertiblePreferredStockMember
           
Series C One Convertible Preferred Stock              
Class Of Stock [Line Items]              
Convertible preferred stock, authorized   4,325,000us-gaap_TemporaryEquitySharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesCOneConvertiblePreferredStockMember
         
Convertible preferred stock, issued   4,275,000us-gaap_TemporaryEquitySharesIssued
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesCOneConvertiblePreferredStockMember
         
Convertible preferred stock, outstanding   4,275,000us-gaap_TemporaryEquitySharesOutstanding
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesCOneConvertiblePreferredStockMember
         
Convertible preferred stock liquidation preference shares $ 2.00us-gaap_TemporaryEquityLiquidationPreferencePerShare
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesCOneConvertiblePreferredStockMember
           
Series D Convertible Preferred Stock              
Class Of Stock [Line Items]              
Convertible preferred stock, authorized   8,300,000us-gaap_TemporaryEquitySharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesDConvertiblePreferredStockMember
         
Convertible preferred stock, issued   7,978,800us-gaap_TemporaryEquitySharesIssued
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesDConvertiblePreferredStockMember
         
Convertible preferred stock, outstanding   7,978,800us-gaap_TemporaryEquitySharesOutstanding
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesDConvertiblePreferredStockMember
         
Convertible preferred stock liquidation preference shares $ 3.00us-gaap_TemporaryEquityLiquidationPreferencePerShare
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesDConvertiblePreferredStockMember
           
Series D One Convertible Preferred Stock              
Class Of Stock [Line Items]              
Convertible preferred stock, authorized   6,300,000us-gaap_TemporaryEquitySharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesDOneConvertiblePreferredStockMember
         
Convertible preferred stock, issued   6,145,667us-gaap_TemporaryEquitySharesIssued
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesDOneConvertiblePreferredStockMember
         
Convertible preferred stock, outstanding   6,145,667us-gaap_TemporaryEquitySharesOutstanding
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesDOneConvertiblePreferredStockMember
         
Convertible preferred stock liquidation preference shares $ 3.00us-gaap_TemporaryEquityLiquidationPreferencePerShare
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesDOneConvertiblePreferredStockMember
           
Series E Convertible Preferred Stock              
Class Of Stock [Line Items]              
Convertible preferred stock, authorized   16,200,000us-gaap_TemporaryEquitySharesAuthorized
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesEConvertiblePreferredStockMember
         
Convertible preferred stock, issued   15,201,716us-gaap_TemporaryEquitySharesIssued
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesEConvertiblePreferredStockMember
         
Convertible preferred stock, outstanding   15,201,716us-gaap_TemporaryEquitySharesOutstanding
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesEConvertiblePreferredStockMember
         
Convertible preferred stock liquidation preference shares $ 2.00us-gaap_TemporaryEquityLiquidationPreferencePerShare
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesEConvertiblePreferredStockMember
           
Common Stock              
Class Of Stock [Line Items]              
Common stock, authorized 250,000,000us-gaap_CommonStockSharesAuthorized
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
150,000,000us-gaap_CommonStockSharesAuthorized
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
         
Common stock shares issued upon conversion from preferred stock         8,029,779us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
   
Preferred stock converted to common, Value 80,000us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
           
Outstanding warrants exercisable         159,834us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
   
Issuance of common stock in connection with exercise of warrants, Shares 9,328amda_IssuanceOfCommonStockUponExerciseOfWarrantsShares
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
178,516amda_IssuanceOfCommonStockUponExerciseOfWarrantsShares
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
         
Common Stock | IPO              
Class Of Stock [Line Items]              
Common stock shares, issued 3,682,900us-gaap_StockIssuedDuringPeriodSharesNewIssues
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_IPOMember
           
Common stock shares issued upon conversion from preferred stock 8,029,779us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_IPOMember
      4,906,874us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_IPOMember
   
Common Stock | Secondary Offering Warrant              
Class Of Stock [Line Items]              
Common stock shares, issued       11,441,646us-gaap_StockIssuedDuringPeriodSharesNewIssues
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_CommonStockMember
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
     
Preferred Stock              
Class Of Stock [Line Items]              
Outstanding warrants exercisable         2,344,731us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_PreferredStockMember
   
Warrant | Secondary Offering Warrant              
Class Of Stock [Line Items]              
Common stock shares, issued 200,000us-gaap_StockIssuedDuringPeriodSharesNewIssues
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_WarrantMember
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
           
Common stock warrants, estimated fair value $ 115,000amda_WarrantClassifiedAsLiabilityFairValueDisclosure
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_WarrantMember
/ us-gaap_SubsidiarySaleOfStockAxis
= amda_SecondaryOfferingWarrantMember
           
Warrant | Series F Convertible Preferred Stock              
Class Of Stock [Line Items]              
Outstanding warrants exercisable           91,951us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_WarrantMember
91,951us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_WarrantMember
Exercise price of warrants $ 0.47amda_ExercisePriceOfWarrants
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_WarrantMember
$ 25.77amda_ExercisePriceOfWarrants
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_WarrantMember
         
Warrant expiration periods           5 years 5 years
Warrant | Series F Convertible Preferred Stock | Placement Agent              
Class Of Stock [Line Items]              
Outstanding warrants exercisable           9,311us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_WarrantMember
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_PrivatePlacementMember
9,311us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_WarrantMember
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_PrivatePlacementMember
Exercise price of warrants $ 0.47amda_ExercisePriceOfWarrants
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_WarrantMember
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_PrivatePlacementMember
$ 56.70amda_ExercisePriceOfWarrants
/ us-gaap_StatementClassOfStockAxis
= amda_SeriesFConvertiblePreferredStockMember
/ us-gaap_StatementEquityComponentsAxis
= us-gaap_WarrantMember
/ us-gaap_SubsidiarySaleOfStockAxis
= us-gaap_PrivatePlacementMember
         
Warrant expiration periods           5 years 5 years