INTERIM CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (Parenthetical) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)
Ordinary Shares [Member]
Changes in equity [Abstract]
Issuance expenses	$ 5,947

Amount of expenses associated with issuance of equity instruments.

No definition available.

Name:	gmda_EquityIssuanceExpenses
Namespace Prefix:	gmda_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration