CONDENSED STATEMENTS OF REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' DEFICIT (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Sep. 30, 2020	Mar. 31, 2020
Series A Redeemable Convertible Preferred Stock
Stock issuance costs		$ 136	$ 22
Series B Redeemable Convertible Preferred Stock
Stock issuance costs	$ 420

The amount of issuance cost associated with the issuance of temporary equity.

No definition available.

Name:	trda_TemporaryEquityIssuanceCosts
Namespace Prefix:	trda_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration