Note 7 - Investments in Marketable Securities (Tables)

6 Months Ended

Mar. 31, 2021

Notes Tables

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

	March 31, 2021						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	$	293,907,000	$	80,246,000	$	213,661,000	$	179,368,000	$	41,775,000	$	137,593,000