XML 13 R1.htm IDEA: XBRL DOCUMENT v3.8.0.1
Document and Entity Information - shares
 9 Months Ended
Mar. 31, 2018
May 11, 2018
Document And Entity Information    
Entity Registrant Name NIOCORP DEVELOPMENTS LTD  
Entity Central Index Key 0001512228  
Document Type 10-Q  
Trading Symbol NIOBF  
Document Period End Date Mar. 31, 2018  
Amendment Flag false  
Current Fiscal Year End Date --06-30  
Is Entity a Well-known Seasoned Issuer? No  
Is Entity a Voluntary Filer? No  
Is Entity's Reporting Status Current? Yes  
Entity Filer Category Non-accelerated Filer  
Entity Common Stock, Shares Outstanding   210,922,398
Document Fiscal Period Focus Q3  
Document Fiscal Year Focus 2018