Quarterly report pursuant to Section 13 or 15(d)

Commitments And Contingencies (Narrative) (Details)

v2.4.1.9
Commitments And Contingencies (Narrative) (Details) (USD $)
In Millions, unless otherwise specified
 1 Months Ended 3 Months Ended
Apr. 30, 2014
Mar. 31, 2015
Purchase Commitment, Excluding Long-term Commitment [Line Items]    
Total unfunded capital commitments   $ 195.2us-gaap_UnrecordedUnconditionalPurchaseObligationBalanceSheetAmount
Purchase commitments payable during the period   90.2us-gaap_UnrecordedUnconditionalPurchaseObligationBalanceOnFirstAnniversary
Deposits paid on options not yet exercised   1.8era_DepositsPaidonOptionsNotYetExercised
Potential reduction amount of liability   102.9era_UnrecordedUnconditionalPurchaseObligationBalanceSheetAmountPotentialAmountToReduceLiability
Liquidated amount liability   2.5era_UnrecordedUnconditionalPurchaseObligationBalanceSheetAmountRelatedToLiquidatedDamage
Aircraft Maintenance Credits Period 4 years  
Aircraft Maintenance Credits Utilized for the Period   $ 1.3era_AircraftMaintenanceCreditsAmountUtilizedforthePeriod
AW189 Heavy Helicopters [Member]    
Purchase Commitment, Excluding Long-term Commitment [Line Items]    
Number of helicopters (in helicopters)   9era_PurchaseCommitmentNumberOfHelicopters
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= era_Aw189HeavyHelicoptersMember
Additional number of helicopters (in helicopters)   10era_PurchaseCommitmentAdditionalNumberOfHelicopters
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= era_Aw189HeavyHelicoptersMember
S92 Heavy Helicopters [Member]    
Purchase Commitment, Excluding Long-term Commitment [Line Items]    
Number of helicopters (in helicopters)   4era_PurchaseCommitmentNumberOfHelicopters
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= era_S92HeavyHelicoptersMember
Additional number of helicopters (in helicopters)   5era_PurchaseCommitmentAdditionalNumberOfHelicopters
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= era_S92HeavyHelicoptersMember
AW169 Light Twin Helicopters [Member]    
Purchase Commitment, Excluding Long-term Commitment [Line Items]    
Number of helicopters (in helicopters)   5era_PurchaseCommitmentNumberOfHelicopters
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= era_Aw169LightTwinHelicoptersMember
Minimum [Member]    
Purchase Commitment, Excluding Long-term Commitment [Line Items]    
Expected Duration of Aircraft Maintenance Credits 12 months  
Maximum [Member]    
Purchase Commitment, Excluding Long-term Commitment [Line Items]    
Expected Duration of Aircraft Maintenance Credits 15 months