Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2024	Jun. 30, 2023
Current
Cash and cash equivalents	$ 2,012	$ 2,341
Prepaid expenses and other	916	1,385
Total current assets	2,928	3,726
Non-current
Deposits	35	35
Investment in equity securities	4	9
Right-of-use assets	181	236
Land and buildings, net	837	839
Mineral properties	16,085	16,085
Total assets	20,070	20,930
Current
Accounts payable and accrued liabilities	1,843	3,491
Warrant liabilities, at fair value	2,365
Convertible debt	7,660
Operating lease liability	96	71
Total current liabilities	11,964	3,562
Non-current
Convertible debt		10,561
Warrant liabilities, at fair value	1,651	4,989
Earnout liability, at fair value	3,817	10,521
Operating lease liability	104	164
Total liabilities	17,536	29,797
Redeemable noncontrolling interest	1,534	2,100
SHAREHOLDERS’ EQUITY (DEFICIT)
Common stock, no par value, unlimited shares authorized; 38,062,647 and 31,202,131 shares outstanding, respectively	163,823	140,421
Accumulated deficit	(161,912)	(150,477)
Accumulated other comprehensive loss	(911)	(911)
Total shareholders’ equity(deficit)	1,000	(10,967)
Total liabilities, redeemable noncontrolling interest, and shareholders’ equity (deficit)	$ 20,070	$ 20,930

The element represents earnout liability at fair value.

No definition available.

Name:	niobf_EarnoutLiabilityAtFairValue
Namespace Prefix:	niobf_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).