Commitment and Contingencies (Details) $ in Thousands	Mar. 31, 2021 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Aggregate consideration paid to NU for agreement obligations	$ 8,343

Aggregate Payments Made To Date For License Agreements

No definition available.

Name:	xcur_AggregatePaymentsMadeToDateForLicenseAgreements
Namespace Prefix:	xcur_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant