CONTRACT ASSETS AND LIABILITIES - Costs, Earnings, Billings, Uncompleted Contracts - (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Jun. 30, 2021
Regulated Operations [Abstract]
Costs incurred on uncompleted contracts	$ 339	$ 295
Estimated earnings	524	568
Costs and estimated earnings on uncompleted contracts	863	863
Less: Billings to date	(878)	(878)
Total costs and estimated earnings on uncompleted contracts	$ (15)	$ (15)

Amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings, net of current billings in excess of costs and estimated earnings on uncompleted contracts

No definition available.

Name:	FONR_TotalCostsAndEstimatedEarningsInExcessOfBillingsOnUncompletedContractsNet
Namespace Prefix:	FONR_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant