Annual report pursuant to Section 13 and 15(d) 12-31-2014

Stock-Based Compensation - Additional Information (Details)

v2.4.1.9
Stock-Based Compensation - Additional Information (Details) (USD $)
1 Months Ended 12 Months Ended
Feb. 28, 2013
Dec. 31, 2014
Dec. 31, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Cash received from option exercises     $ 77,000us-gaap_ProceedsFromStockOptionsExercised
Number of stock options granted during the period   1,448,751us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod  
Stock-based compensation expense   11,001,000us-gaap_AllocatedShareBasedCompensationExpense 555,000us-gaap_AllocatedShareBasedCompensationExpense
Employee Stock Option      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Weighted average grant date fair value of options granted   $ 1.67us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockOptionMember
$ 0.07us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockOptionMember
Intrinsic value of options exercised   0us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockOptionMember
900,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockOptionMember
Cash received from option exercises   0us-gaap_ProceedsFromStockOptionsExercised
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockOptionMember
77,000us-gaap_ProceedsFromStockOptionsExercised
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockOptionMember
Tax benefit related to options exercised   0us-gaap_DeferredTaxExpenseFromStockOptionsExercised
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockOptionMember
0us-gaap_DeferredTaxExpenseFromStockOptionsExercised
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockOptionMember
Number of stock options granted during the period   0us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod
/ us-gaap_AwardTypeAxis
= us-gaap_EmployeeStockOptionMember
 
Restricted stock units      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Fair value of shares vested   3,000,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
110,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
Number of stock options exchanged for RSUs 93,968amda_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInStockOptionExchangeInPeriod
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
   
Incremental fair value   758,000amda_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInStockOptionExchangeInPeriodFairValueIncremental
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
 
Restricted stock units granted during period   1,815,259us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
/ us-gaap_AwardTypeAxis
= us-gaap_RestrictedStockUnitsRSUMember
 
Stock Options to Non-employees      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Number of stock options granted during the period   165,387us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod
/ us-gaap_AwardTypeAxis
= us-gaap_StockCompensationPlanMember
13,191us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod
/ us-gaap_AwardTypeAxis
= us-gaap_StockCompensationPlanMember
Stock-based compensation expense   $ 712,000us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_AwardTypeAxis
= us-gaap_StockCompensationPlanMember
$ 248,000us-gaap_AllocatedShareBasedCompensationExpense
/ us-gaap_AwardTypeAxis
= us-gaap_StockCompensationPlanMember
Stock Options to Non-employees | Restricted stock units      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Restricted stock units granted during period   94,560us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
/ us-gaap_AwardTypeAxis
= us-gaap_StockCompensationPlanMember
/ us-gaap_StatementClassOfStockAxis
= us-gaap_RestrictedStockMember
13,121us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
/ us-gaap_AwardTypeAxis
= us-gaap_StockCompensationPlanMember
/ us-gaap_StatementClassOfStockAxis
= us-gaap_RestrictedStockMember
2012 Plan      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Shares issuable with respect to awards granted   3,000,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
/ us-gaap_PlanNameAxis
= amda_TwoThousandTwelvePlanMember
 
Shares available for grant   113,914us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
/ us-gaap_PlanNameAxis
= amda_TwoThousandTwelvePlanMember