Note 16 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Income Tax Expense (Benefit)	$ (3,153)	$ (17,550)	$ 1,350
Effective Income Tax Rate Reconciliation, Repatriation of Foreign Earnings, Amount	5,200
Amount of Benefit Offset by State Income Taxes, Net of the Federal Benefit	2,000
Undistributed Earnings of Foreign Subsidiaries	899,700
Deferred Income Tax Assets, Net	837	571
Deferred Tax Assets, Valuation Allowance	47,865	8,348
Decrease in Unrecognized Tax Benefits is Reasonably Possible	300
Domestic Tax Jurisdiction [Member]
Deferred Tax Assets, Valuation Allowance	5,600
Operating Loss Carryforwards	5,800
Foreign Tax Jurisdiction [Member]
Deferred Tax Assets, Valuation Allowance	40,200
Operating Loss Carryforwards	42,200
Foreign Tax Jurisdiction [Member] | Luxembourg Inland Revenue [Member]
Deferred Tax Assets, Valuation Allowance	29,500
State and Local Jurisdiction [Member]
Operating Loss Carryforwards	1,600
Intercompany Profit Elimination [Member]
Deferred Income Tax Assets, Net	600	$ 600
Changes in Foreign Exchange Rates [Member]
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	(2,900)
GERMANY
Foreign Earnings Repatriated	455,000
Income Tax Expense (Benefit)	$ (3,200)