Note 11 - Operating Segments - Summarized Financial Information for Reportable Segments (Details) - USD ($)	1 Months Ended	3 Months Ended						9 Months Ended
	Jan. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Jun. 30, 2021	Jun. 30, 2020	Sep. 30, 2020
Revenue from Contract with Customer, Including Assessed Tax		$ 13,562,000			$ 12,874,000			$ 37,952,000	$ 36,907,000
Operating expenses		12,238,000			12,281,000			35,638,000	38,930,000
Income from operations		1,324,000			593,000			2,314,000	(2,023,000)
Dividends and interest income		776,000			1,596,000			2,063,000	4,573,000
Other income		69,000			0			69,000	3,000
Realized gains on sales of marketable securities	$ 18,478,000							18,478,000	0
Net unrealized gains on marketable securities		55,686,000			16,489,000			131,754,000	(41,191,000)
Interest expense on debt		(68,000)						(196,000)
Pretax income		57,773,000			18,594,000			154,434,000	(39,102,000)
Income tax provisions		(15,200,000)			(4,320,000)			(40,115,000)	11,260,000
Net income (loss)		42,573,000	$ 12,476,000	$ 59,270,000	14,274,000	$ (56,326,000)	$ 14,210,000	114,319,000	(27,842,000)
Total assets		389,500,000			197,964,000			389,500,000	197,964,000	$ 238,575,000
Capital expenditures		0			0			29,000	168,000
Other income		69,000			0			69,000	3,000
Net unrealized gains (losses) on marketable securities					16,489,000			131,754,000	(41,191,000)
Pretax loss		57,773,000			18,594,000			154,434,000	(39,102,000)
Real Estate Bank Loan Secured by Logan Office [Member]
Interest expense on debt		(14,000)			(20,000)			(48,000)	(63,000)
Margin Account [Member]
Interest expense on debt		(68,000)			(64,000)			(196,000)	(401,000)
Advertising [Member]
Revenue from Contract with Customer, Including Assessed Tax		2,195,000			1,297,000			5,649,000	5,415,000
Subscription and Circulation [Member]
Revenue from Contract with Customer, Including Assessed Tax		1,126,000			1,259,000			3,458,000	3,857,000
Advertising Service Fees and Other [Member]
Revenue from Contract with Customer, Including Assessed Tax		762,000			575,000			1,964,000	1,923,000
License and Maintenance [Member]
Revenue from Contract with Customer, Including Assessed Tax		5,602,000			5,531,000			16,990,000	16,246,000
Consulting Fees [Member]
Revenue from Contract with Customer, Including Assessed Tax		2,100,000			3,147,000			4,649,000	5,065,000
Service, Other [Member]
Revenue from Contract with Customer, Including Assessed Tax		1,777,000			1,065,000			5,242,000	4,401,000
Traditional Business [Member]
Revenue from Contract with Customer, Including Assessed Tax		4,083,000			3,131,000			11,071,000	11,195,000
Journal Technologies [Member]
Revenue from Contract with Customer, Including Assessed Tax		9,479,000			9,743,000			26,881,000	25,712,000
Operating Segments [Member] | Traditional Business [Member]
Operating expenses		3,665,000			3,699,000			11,001,000	11,319,000
Income from operations		418,000			(568,000)			70,000	(124,000)
Dividends and interest income		0			0			0	0
Other income		0						0	0
Realized gains on sales of marketable securities								0
Net unrealized gains on marketable securities		0						0
Interest expense on debt		0						0
Pretax income		418,000			(568,000)			70,000	(124,000)
Income tax provisions		(175,000)			125,000			(15,000)	15,000
Net income (loss)		243,000			(443,000)			55,000	(109,000)
Total assets		17,894,000			17,752,000			17,894,000	17,752,000
Capital expenditures		0			0			22,000	99,000
Other income		0						0	0
Net unrealized gains (losses) on marketable securities					0				0
Pretax loss		418,000			(568,000)			70,000	(124,000)
Operating Segments [Member] | Traditional Business [Member] | Real Estate Bank Loan Secured by Logan Office [Member]
Interest expense on debt		0			0			0	0
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		2,195,000			1,297,000			5,649,000	5,415,000
Operating Segments [Member] | Traditional Business [Member] | Subscription and Circulation [Member]
Revenue from Contract with Customer, Including Assessed Tax		1,126,000			1,259,000			3,458,000	3,857,000
Operating Segments [Member] | Traditional Business [Member] | Advertising Service Fees and Other [Member]
Revenue from Contract with Customer, Including Assessed Tax		762,000			575,000			1,964,000	1,923,000
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		8,573,000			8,582,000			24,637,000	27,611,000
Income from operations		906,000			1,161,000			2,244,000	(1,899,000)
Dividends and interest income		0			0			0	0
Other income		0						0	0
Realized gains on sales of marketable securities								0
Net unrealized gains on marketable securities		0						0
Interest expense on debt		0						0
Pretax income		906,000			1,161,000			2,244,000	(1,899,000)
Income tax provisions		(460,000)			(545,000)			(785,000)	380,000
Net income (loss)		446,000			616,000			1,459,000	(1,519,000)
Total assets		21,498,000			24,667,000			21,498,000	24,667,000
Capital expenditures		0			0			7,000	69,000
Other income		0						0	0
Net unrealized gains (losses) on marketable securities					0				0
Pretax loss		906,000			1,161,000			2,244,000	(1,899,000)
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		5,602,000			5,531,000			16,990,000	16,246,000
Operating Segments [Member] | Journal Technologies [Member] | Consulting Fees [Member]
Revenue from Contract with Customer, Including Assessed Tax		2,100,000			3,147,000			4,649,000	5,065,000
Operating Segments [Member] | Journal Technologies [Member] | Service, Other [Member]
Revenue from Contract with Customer, Including Assessed Tax		1,777,000			1,065,000			5,242,000	4,401,000
Corporate, Non-Segment [Member]
Operating expenses		0			0			0	0
Income from operations		0			0			0	0
Dividends and interest income		776,000			1,596,000			2,063,000	4,573,000
Other income		69,000						69,000	3,000
Realized gains on sales of marketable securities								18,478,000
Net unrealized gains on marketable securities		55,686,000						131,754,000
Interest expense on debt		(68,000)						(196,000)
Pretax income		56,449,000			18,001,000			152,120,000	(37,079,000)
Income tax provisions		(14,565,000)			(3,900,000)			(39,315,000)	10,865,000
Net income (loss)		41,884,000			14,101,000			112,805,000	(26,214,000)
Total assets		350,108,000			155,545,000			350,108,000	155,545,000
Capital expenditures		0			0			0	0
Other income		69,000						69,000	3,000
Net unrealized gains (losses) on marketable securities					16,489,000				(41,191,000)
Pretax loss		56,449,000			18,001,000			152,120,000	(37,079,000)
Corporate, Non-Segment [Member] | Real Estate Bank Loan Secured by Logan Office [Member]
Interest expense on debt		(14,000)			(20,000)			(48,000)	(63,000)
Corporate, Non-Segment [Member] | Margin Account [Member]
Interest expense on debt					(64,000)				(401,000)
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