Fair Value of Financial Instruments - Additional Information (Detail) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2016
Fair Value Disclosures [Abstract]
Transfers of assets or liabilities	$ 0	$ 0

Fair Value Assets Liabilities Transfer Between Levels

No definition available.

Name:	ebio_FairValueAssetsLiabilitiesTransferBetweenLevels
Namespace Prefix:	ebio_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration