Note 8 - Investments in Marketable Securities (Tables)

6 Months Ended

Mar. 31, 2024

Notes Tables

Schedule of Available-for-Sale Securities Reconciliation [Table Text Block]

	March 31, 2024						September 30, 2023
	Aggregate fair value		Amortized/ Adjusted cost basis		Pretax unrealized gains		Aggregate fair value		Amortized/ Adjusted cost basis		Pretax unrealized gains
Marketable securities Common stocks	$	297,003,000	$	139,094,000	$	157,909,000	$	303,128,000	$	165,412,000	$	137,716,000