Note 8 - Investments in Marketable Securities (Tables)

3 Months Ended

Dec. 31, 2022

Notes Tables

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

	December 31, 2022						September 30, 2022
	Aggregate fair value		Amortized/ Adjusted cost basis		Pretax unrealized gains		Aggregate fair value		Amortized/ Adjusted cost basis		Pretax unrealized gains
Marketable securities
Common stocks	$	307,151,000	$	162,434,000	$	144,717,000	$	275,529,000	$	154,837,000	$	120,692,000