Merger - Schedule of Milestone Payment Liability (Details) $ in Thousands	9 Months Ended
Mar. 31, 2022 USD ($)
Business Combinations [Abstract]
Balance	$ 182
Change in fair value estimate	(10)
Balance	$ 172

Milestone payment liability change in fair value estimate.

No definition available.

Name:	ktra_MilestonePaymentLiabilityChangeInFairValueEstimate
Namespace Prefix:	ktra_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration