Note 3 - Business Combination - Business Combination Purchase Price Allocation (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Mar. 31, 2025	Jun. 15, 2024
Goodwill	$ 12,280	$ 12,280
Amplex Holdings [Member]
Cash and cash equivalents			$ 221
Accounts receivable			116
Materials and supplies			537
Operating lease right-of-use			3,063
Prepaid expenses and other assets			265
Property, plant, and equipment			24,584
Intangible assets			4,133
Goodwill			12,280
Total assets acquired			45,199
Accounts payable			1,252
Accrued expenses and other liabilities			112
Lease liabilities			3,063
Deferred income taxes			4,208
Deferred revenue			556
Total liabilities assumed			9,191
Total fair value of net assets acquired			36,008
Less: redeemable noncontrolling interest			(17,644)
Total Adjusted Base Purchase Price			$ 18,364