Note 2 - Summary of Significant Accounting Policies (Tables)

12 Months Ended

Sep. 30, 2017

Notes Tables

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

	September 30, 20 17						September 30, 201 6
	Aggregate fair value		Amortized/ Adjusted cost basis		Pretax unrealized gains		Aggregate fair value		Amortized/ Adjusted cost basis		Pretax unrealized gains
Marketable securities
Common stocks	$	220,973,000	$	58,449,000	$	162,524,000	$	158,462,000	$	53,436,000	$	105,026,000
Bonds		8,292,000		4,944,000		3,348,000		8,172,000		4,942,000		3,230,000
	$	229,265,000	$	63,393,000	$	165,872,000	$	166,634,000	$	58,378,000	$	108,256,000

Schedule of Finite-Lived Intangible Assets [Table Text Block]

	September 30, 201 7									September 30, 201 6
	Customer Relationships			Developed Technology			Total			Customer Relationships			Developed Technology			Total
Gross intangible	$	21,950,000		$	2,525,000		$	24,475,000		$	22,104,000		$	2,525,000		$	24,629,000
Accumulated amortization		(19,174,000	)		(2,243,000	)		(21,417,000	)		(14,938,000	)		(1,738,000	)		(16,676,000	)
	$	2,776,000		$	282,000		$	3,058,000		$	7,166,000		$	787,000		$	7,953,000

Valuation and Qualifying Accounts [Table Text Block]

Description	Balance at Beginning of Year		Additions Charged to Costs and Expenses		Accounts Charged off less Recoveries			Balance at End of Year
Fiscal 2017
Allowance for doubtful accounts	$	200,000	$	33,000	$	(33,000	)	$	200,000
Fiscal 2016
Allowance for doubtful accounts	$	250,000	$	5,000	$	(55,000	)	$	200,000
Fiscal 2015
Allowance for doubtful accounts	$	250,000	$	61,000	$	(61,000	)	$	250,000