Quaterly financial data (Unaudited) (Details 2) - USD ($)	3 Months Ended	6 Months Ended		12 Months Ended
	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021	Jun. 30, 2022	Jun. 30, 2021
Balance, amount	$ 17,538,100	$ 17,538,100	$ 26,224,800	$ 26,224,800	$ 11,721,400
Net loss		(4,079,400)	(2,105,300)	(13,668,100)	(3,672,500)
Foreign currency translation gain (loss)		88,600	104,000	(86,200)	(9,200)
Unrealized holding loss on investment securities, net of tax				(10,200)
Stock-based compensation		1,236,700		2,350,600	2,108,000
Balance, amount		14,792,600		17,538,100	26,224,800
Effect of Restatement [Member]
Balance, amount	(8,023,700)	(8,023,700)
Net loss	(417,200)			(8,023,700)
Balance, amount	(8,440,900)			(8,023,700)
Effect of Restatement [Member] | Common Stocks [Member]
Net loss				0
Effect of Restatement [Member] | Retained Earning (Accumulated Deficit) [Member]
Net loss	(417,200)			(8,023,700)
As Filed [Member]
Balance, amount	25,561,800	25,561,800	26,224,800	26,224,800
Net loss	(1,292,000)			(5,644,400)
Foreign currency translation gain (loss)	(118,300)			(86,200)
Unrealized holding loss on investment securities, net of tax	4,100			(10,200)
Stock-based compensation	618,100			2,350,600
Balance, amount	24,773,700			25,561,800	26,224,800
As Filed [Member] | Common Stocks [Member]
Balance, amount	351,200	$ 351,200	$ 324,000	324,000
Balance, amount	$ 351,200			$ 351,200	$ 324,000
Balance, shares	7,023,401	7,023,401	6,477,945	6,477,945
Balance, shares	7,023,401			7,023,401	6,477,945
As Filed [Member] | Treasury Stocks [Member]
Balance, amount	$ 52,400	$ 52,400	$ 52,400	$ 52,400
Balance, amount	$ 52,400			$ 52,400	$ 52,400
Balance, shares	19,802	19,802	19,802	19,802
Balance, shares	19,802			19,802	19,802
As Filed [Member] | Additional Paids-In Capital [Member]
Balance, amount	$ 31,664,100	$ 31,664,100	$ 26,613,500	$ 26,613,500
Stock-based compensation	618,100			2,350,600
Balance, amount	32,282,200			31,664,100	$ 26,613,500
As Filed [Member] | Accumulated others comprehensive loss [Member]
Balance, amount	(105,600)	(105,600)	(9,200)	(9,200)
Foreign currency translation gain (loss)	(118,300)			(86,200)
Unrealized holding loss on investment securities, net of tax	4,100			(10,200)
Balance, amount	(219,800)			(105,600)	(9,200)
As Filed [Member] | Retained Earning (Accumulated Deficit) [Member]
Balance, amount	(6,295,500)	(6,295,500)	$ (651,100)	(651,100)
Net loss	(1,292,000)			(13,668,100)
Balance, amount	(7,587,500)			(6,295,500)	$ (651,100)
As Restated [Member]
Balance, amount	17,538,100	17,538,100
Net loss	(1,709,200)			(13,668,100)
Foreign currency translation gain (loss)	(118,300)			(86,200)
Balance, amount	16,332,800			17,538,100
As Restated [Member] | Common Stocks [Member]
Balance, amount	351,200	$ 351,200
Balance, amount	$ 351,200			$ 351,200
Balance, shares	7,023,401	7,023,401
Balance, shares	7,023,401			7,023,401
As Restated [Member] | Treasury Stocks [Member]
Balance, amount	$ 52,400	$ 52,400
Balance, amount	$ 52,400			$ 52,400
Balance, shares	19,802	19,802
Balance, shares	19,802			19,802
As Restated [Member] | Additional Paids-In Capital [Member]
Balance, amount	$ 31,664,100	$ 31,664,100
Balance, amount	32,282,200			$ 31,664,100
As Restated [Member] | Accumulated others comprehensive loss [Member]
Balance, amount	(105,600)	(105,600)
Balance, amount	(219,800)			(105,600)
As Restated [Member] | Retained Earning (Accumulated Deficit) [Member]
Balance, amount	(14,319,200)	$ (14,319,200)
Balance, amount	$ (16,028,400)			$ (14,319,200)