Variable Interest Entities - Schedule of Carrying Amounts of Assets and Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025
Current assets
Cash and cash equivalents	$ 39,557	$ 39,439
Trade and other receivables:
Joint interest billings	1,763	8,191
ATO receivable	1,687	1,219
Other receivable	757	222
Prepaid expenses and other current assets	2,696	1,903
Total current assets	46,460	56,696
Operating lease right-of-use assets	4,199	1,549
Finance lease right-of-use assets	14,144	16,544
Prepaid expenses and other non-current assets	5,344	4,610
Total non-current assets	437,705	389,766
TOTAL ASSETS	484,164	446,462
Current liabilities
Accounts payable and accrued expenses	31,121	20,457
Current portion of operating lease obligations	2,472	391
Current portion of finance lease obligations	14,782	15,307
Advance against joint interest billings	1,943	450
Total current liabilities	50,318	36,605
Operating lease obligations	1,795	1,175
Finance lease obligations	6,561	9,523
Asset retirement obligations	10,053	9,649
Total non-current liabilities	18,477	20,404
Total liabilities	68,796	57,009
Unproved properties
Trade and other receivables:
Natural gas properties, successful efforts method:	378,802	342,314
Assets under construction - natural gas equipment
Trade and other receivables:
Natural gas properties, successful efforts method:	34,868	24,441
Variable interest entity, primary beneficiary | Tamboran (B1) Pty Ltd ("TB1")
Current assets
Cash and cash equivalents	13,109	3,729
Trade and other receivables:
Joint interest billings	1,763	8,191
Intercompany receivable	0	1,934
ATO receivable	1,118	722
Other receivable	179	113
Prepaid expenses and other current assets	205	0
Total current assets	16,374	14,690
Operating lease right-of-use assets	2,739	0
Finance lease right-of-use assets	14,144	16,544
Prepaid expenses and other non-current assets	2,081	2,026
Total non-current assets	340,779	304,201
TOTAL ASSETS	357,153	318,891
Current liabilities
Accounts payable and accrued expenses	21,163	12,507
Current portion of operating lease obligations	2,063	0
Current portion of finance lease obligations	14,782	15,307
Total current liabilities	38,008	27,814
Operating lease obligations	722	0
Finance lease obligations	6,561	9,523
Asset retirement obligations	5,370	5,127
Loan from Group	180,361	163,016
Total non-current liabilities	193,014	177,666
Total liabilities	231,022	205,480
Variable interest entity, primary beneficiary | Tamboran SPCF Pty Ltd (“TR SPCF")
Current assets
Cash and cash equivalents	5,940	1,935
Trade and other receivables:
ATO receivable	262	123
Loan to Tamboran	0	1,124
Total current assets	6,202	3,182
Prepaid expenses and other non-current assets	716	0
Total non-current assets	35,584	24,441
TOTAL ASSETS	41,786	27,623
Current liabilities
Accounts payable and accrued expenses	6,860	4,364
Advance against joint interest billings	1,943	450
Intercompany Payable	2,207	1,338
Total current liabilities	11,010	6,152
Asset retirement obligations	98	95
Total non-current liabilities	98	95
Total liabilities	11,108	6,247
Variable interest entity, primary beneficiary | Unproved properties | Tamboran (B1) Pty Ltd ("TB1")
Trade and other receivables:
Natural gas properties, successful efforts method:	321,815	285,631
Variable interest entity, primary beneficiary | Assets under construction - natural gas equipment | Tamboran SPCF Pty Ltd (“TR SPCF")
Trade and other receivables:
Natural gas properties, successful efforts method:	$ 34,868	$ 24,441