Note 11 - Operating Segments - Summarized Financial Information for Reportable Segments (Details) - USD ($)	1 Months Ended	3 Months Ended				6 Months Ended
	Jan. 31, 2021	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2021	Mar. 31, 2020	Sep. 30, 2020
Revenue from Contract with Customer, Including Assessed Tax		$ 13,970,000		$ 12,356,000		$ 24,390,000	$ 24,033,000
Operating expenses		12,665,000		13,454,000		23,400,000	26,649,000
Income (loss) from operations		1,305,000		(1,098,000)		990,000	(2,616,000)
Dividends and interest income		649,000		1,297,000		1,287,000	2,977,000
Realized gains on sales of marketable securities	$ 18,478,000	18,478,000		0		18,478,000	0
Net unrealized losses on marketable securities		(5,144,000)		(77,211,000)		76,068,000	(57,680,000)
Interest expense on debt		(64,000)				(128,000)
Pretax income (loss)		15,211,000		(77,186,000)		96,661,000	(57,696,000)
Income tax (provisions) benefits		(2,735,000)		20,860,000		(24,915,000)	15,580,000
Net income (loss)		12,476,000	$ 59,270,000	(56,326,000)	$ 14,210,000	71,746,000	(42,116,000)
Total assets		330,645,000		174,735,000		330,645,000	174,735,000	$ 238,575,000
Capital expenditures		29,000		71,000		29,000	168,000
Other income						0	3,000
Marketable Securities, Unrealized Gain (Loss), Total		(5,144,000)		(77,211,000)		76,068,000	(57,680,000)
Real Estate Bank Loan Secured by Logan Office [Member]
Interest expense on debt		(13,000)		(21,000)		(34,000)	(43,000)
Margin Account [Member]
Interest expense on debt		(64,000)		(153,000)		(128,000)	(337,000)
Advertising [Member]
Revenue from Contract with Customer, Including Assessed Tax		1,762,000		1,992,000		3,454,000	4,118,000
Subscription and Circulation [Member]
Revenue from Contract with Customer, Including Assessed Tax		1,129,000		1,286,000		2,332,000	2,598,000
Advertising Service Fees and Other [Member]
Revenue from Contract with Customer, Including Assessed Tax		568,000		654,000		1,202,000	1,348,000
License and Maintenance [Member]
Revenue from Contract with Customer, Including Assessed Tax		6,355,000		5,505,000		11,388,000	10,715,000
Consulting Fees [Member]
Revenue from Contract with Customer, Including Assessed Tax		2,305,000		1,229,000		2,549,000	1,918,000
Service, Other [Member]
Revenue from Contract with Customer, Including Assessed Tax		1,851,000		1,690,000		3,465,000	3,336,000
Traditional Business [Member]
Revenue from Contract with Customer, Including Assessed Tax		3,459,000		3,932,000		6,988,000	8,064,000
Journal Technologies [Member]
Revenue from Contract with Customer, Including Assessed Tax		10,511,000		8,424,000		17,402,000	15,969,000
Operating Segments [Member] | Traditional Business [Member]
Operating expenses		4,355,000		3,762,000		7,336,000	7,620,000
Income (loss) from operations		(896,000)		170,000		(348,000)	444,000
Dividends and interest income		0		0		0	0
Realized gains on sales of marketable securities		0				0
Net unrealized losses on marketable securities		0		0		0	0
Interest expense on debt		0				0
Pretax income (loss)		(909,000)		149,000		(382,000)	401,000
Income tax (provisions) benefits		265,000		(40,000)		160,000	(110,000)
Net income (loss)		(644,000)		109,000		(222,000)	291,000
Total assets		14,586,000		16,074,000		14,586,000	16,074,000
Capital expenditures		22,000		64,000		22,000	99,000
Other income							0
Marketable Securities, Unrealized Gain (Loss), Total		0		0		0	0
Operating Segments [Member] | Traditional Business [Member] | Real Estate Bank Loan Secured by Logan Office [Member]
Interest expense on debt		(13,000)		(21,000)		(34,000)	(43,000)
Operating Segments [Member] | Traditional Business [Member] | Margin Account [Member]
Interest expense on debt				0			0
Operating Segments [Member] | Traditional Business [Member] | Advertising [Member]
Revenue from Contract with Customer, Including Assessed Tax		1,762,000		1,992,000		3,454,000	4,118,000
Operating Segments [Member] | Traditional Business [Member] | Subscription and Circulation [Member]
Revenue from Contract with Customer, Including Assessed Tax		1,129,000		1,286,000		2,332,000	2,598,000
Operating Segments [Member] | Traditional Business [Member] | Advertising Service Fees and Other [Member]
Revenue from Contract with Customer, Including Assessed Tax		568,000		654,000		1,202,000	1,348,000
Operating Segments [Member] | Traditional Business [Member] | License and Maintenance [Member]
Revenue from Contract with Customer, Including Assessed Tax		0		0		0	0
Operating Segments [Member] | Traditional Business [Member] | Consulting Fees [Member]
Revenue from Contract with Customer, Including Assessed Tax		0		0		0	0
Operating Segments [Member] | Traditional Business [Member] | Service, Other [Member]
Revenue from Contract with Customer, Including Assessed Tax		0		0		0	0
Operating Segments [Member] | Journal Technologies [Member]
Operating expenses		8,310,000		9,692,000		16,064,000	19,029,000
Income (loss) from operations		2,201,000		(1,268,000)		1,338,000	(3,060,000)
Dividends and interest income		0		0		0	0
Realized gains on sales of marketable securities		0				0
Net unrealized losses on marketable securities		0		0		0	0
Interest expense on debt		0				0
Pretax income (loss)		2,201,000		(1,268,000)		1,338,000	(3,060,000)
Income tax (provisions) benefits		(730,000)		415,000		(325,000)	925,000
Net income (loss)		1,471,000		(853,000)		1,013,000	(2,135,000)
Total assets		21,639,000		19,578,000		21,639,000	19,578,000
Capital expenditures		7,000		7,000		7,000	69,000
Other income							0
Marketable Securities, Unrealized Gain (Loss), Total		0		0		0	0
Operating Segments [Member] | Journal Technologies [Member] | Real Estate Bank Loan Secured by Logan Office [Member]
Interest expense on debt		0		0		0	0
Operating Segments [Member] | Journal Technologies [Member] | Margin Account [Member]
Interest expense on debt				0			0
Operating Segments [Member] | Journal Technologies [Member] | Advertising [Member]
Revenue from Contract with Customer, Including Assessed Tax		0		0		0	0
Operating Segments [Member] | Journal Technologies [Member] | Subscription and Circulation [Member]
Revenue from Contract with Customer, Including Assessed Tax		0		0		0	0
Operating Segments [Member] | Journal Technologies [Member] | Advertising Service Fees and Other [Member]
Revenue from Contract with Customer, Including Assessed Tax		0		0		0	0
Operating Segments [Member] | Journal Technologies [Member] | License and Maintenance [Member]
Revenue from Contract with Customer, Including Assessed Tax		6,355,000		5,505,000		11,388,000	10,715,000
Operating Segments [Member] | Journal Technologies [Member] | Consulting Fees [Member]
Revenue from Contract with Customer, Including Assessed Tax		2,305,000		1,229,000		2,549,000	1,918,000
Operating Segments [Member] | Journal Technologies [Member] | Service, Other [Member]
Revenue from Contract with Customer, Including Assessed Tax		1,851,000		1,690,000		3,465,000	3,336,000
Corporate, Non-Segment [Member]
Operating expenses		0		0		0	0
Income (loss) from operations		0		0		0	0
Dividends and interest income		649,000		1,297,000		1,287,000	2,977,000
Realized gains on sales of marketable securities		18,478,000				18,478,000
Net unrealized losses on marketable securities		(5,144,000)		(77,211,000)		76,068,000	(57,680,000)
Interest expense on debt		(64,000)				(128,000)
Pretax income (loss)		13,919,000		(76,067,000)		95,705,000	(55,037,000)
Income tax (provisions) benefits		(2,270,000)		20,485,000		(24,750,000)	14,765,000
Net income (loss)		11,649,000		(55,582,000)		70,955,000	(40,272,000)
Total assets		294,420,000		139,083,000		294,420,000	139,083,000
Capital expenditures		0		0		0	0
Other income							3,000
Marketable Securities, Unrealized Gain (Loss), Total		(5,144,000)		(77,211,000)		76,068,000	(57,680,000)
Corporate, Non-Segment [Member] | Real Estate Bank Loan Secured by Logan Office [Member]
Interest expense on debt		0		0		0	0
Corporate, Non-Segment [Member] | Margin Account [Member]
Interest expense on debt				(153,000)			(337,000)
Corporate, Non-Segment [Member] | Advertising [Member]
Revenue from Contract with Customer, Including Assessed Tax		0		0		0	0
Corporate, Non-Segment [Member] | Subscription and Circulation [Member]
Revenue from Contract with Customer, Including Assessed Tax		0		0		0	0
Corporate, Non-Segment [Member] | Advertising Service Fees and Other [Member]
Revenue from Contract with Customer, Including Assessed Tax		0		0		0	0
Corporate, Non-Segment [Member] | License and Maintenance [Member]
Revenue from Contract with Customer, Including Assessed Tax		0		0		0	0
Corporate, Non-Segment [Member] | Consulting Fees [Member]
Revenue from Contract with Customer, Including Assessed Tax		0		0		0	0
Corporate, Non-Segment [Member] | Service, Other [Member]
Revenue from Contract with Customer, Including Assessed Tax		$ 0		$ 0		$ 0	$ 0