XML 124 R74.htm IDEA: XBRL DOCUMENT
v3.25.2

COMMON SHARES (Details 13) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Jun. 30, 2025 | Jun. 30, 2024
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Fair value of Warrants issued | $ 144 |
Warrant Liability [Member] |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Initial valuation, at begining | 2,365 |
Fair value of Warrants issued | (2,262) |
Gain on issuance of Warrants | (103) |
Valuation, at ending |  | $ 2,365

X
- Definition The element represents changes in fair value of initial valuation. + References No definition available. + Details
Name: | niobf_ChangesInFairValueOfInitialValuation
Namespace Prefix: | niobf_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition The element represents gain on issuance of warrants. + References No definition available. + Details
Name: | niobf_GainOnIssuanceOfWarrants
Namespace Prefix: | niobf_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480870/815-30-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480870/815-30-50-2 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480870/815-30-50-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480870/815-30-50-2 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482765/220-10-50-4 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482765/220-10-50-5 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 830 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481674/830-30-50-1 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 830 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481694/830-30-45-17 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 830 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 20 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481694/830-30-45-20 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Topic 830 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 20 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481694/830-30-45-20 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Topic 830 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 20 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481694/830-30-45-20 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Topic 830 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 20 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481694/830-30-45-20 + Details
Name: | us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of expense (income) related to adjustment to fair value of warrant liability. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (b) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-28 + Details
Name: | us-gaap_FairValueAdjustmentOfWarrants
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=niobf_WarrantLiabilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |