Note 7 - Investments in Marketable Securities (Tables)

3 Months Ended

Dec. 31, 2020

Notes Tables

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

	December 31, 2020						September 30, 2020
	Aggregate fair value		Amortized/ Adjusted cost basis		Pretax unrealized gains		Aggregate fair value		Amortized/ Adjusted cost basis		Pretax unrealized gains
Marketable securities
Common stocks	$	260,580,000	$	41,775,000	$	218,805,000	$	179,368,000	$	41,775,000	$	137,593,000