Mergers - Contingent Value Rights Agreement (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Mar. 23, 2021	Dec. 31, 2019
Merger Related Agreements
Percentage of proceeds from the grant, sale, or transfer of rights		10.00%	80.00%
Amount of milestones accrued	$ 0

Refers to percentage of proceeds from grant sale or transfer of rights.

No definition available.

Name:	nrbo_PercentageOfProceedsFromGrantSaleOrTransferOfRights
Namespace Prefix:	nrbo_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant