Condensed Consolidated Statements of Shareholders' Equity - USD ($)	Total	Capital in Excess of Par Value [Member]	Retained Earnings [Member]	Common Stock [Member] Common Stock [Member]	Class B Stock [Member] Common Stock [Member]
Beginning balance at Sep. 30, 2022	$ 166,917,000	$ 12,590,000	$ 152,861,000	$ 1,234,000	$ 232,000
Beginning balance, shares at Sep. 30, 2022				12,338,845	2,318,857
Net Income (Loss)	3,476,000		3,476,000
Ending balance at Dec. 31, 2022	170,393,000	12,590,000	156,337,000	$ 1,234,000	$ 232,000
Ending balance, shares at Dec. 31, 2022				12,338,845	2,318,857
Beginning balance at Sep. 30, 2022	166,917,000	12,590,000	152,861,000	$ 1,234,000	$ 232,000
Beginning balance, shares at Sep. 30, 2022				12,338,845	2,318,857
Net Income (Loss)	11,561,000
Ending balance at Jun. 30, 2023	178,478,000	12,590,000	164,422,000	$ 1,234,000	$ 232,000
Ending balance, shares at Jun. 30, 2023				12,338,845	2,318,857
Beginning balance at Dec. 31, 2022	170,393,000	12,590,000	156,337,000	$ 1,234,000	$ 232,000
Beginning balance, shares at Dec. 31, 2022				12,338,845	2,318,857
Net Income (Loss)	4,873,000		4,873,000
Ending balance at Mar. 31, 2023	175,266,000	12,590,000	161,210,000	$ 1,234,000	$ 232,000
Ending balance, shares at Mar. 31, 2023				12,338,845	2,318,857
Net Income (Loss)	3,212,000		3,212,000
Ending balance at Jun. 30, 2023	178,478,000	12,590,000	164,422,000	$ 1,234,000	$ 232,000
Ending balance, shares at Jun. 30, 2023				12,338,845	2,318,857
Beginning balance at Sep. 30, 2023	181,583,000	12,590,000	167,527,000	$ 1,234,000	$ 232,000
Beginning balance, shares at Sep. 30, 2023				12,338,845	2,318,857
Net Income (Loss)	4,326,000		4,326,000
Ending balance at Dec. 31, 2023	185,909,000	12,590,000	171,853,000	$ 1,234,000	$ 232,000
Ending balance, shares at Dec. 31, 2023				12,338,845	2,318,857
Beginning balance at Sep. 30, 2023	181,583,000	12,590,000	167,527,000	$ 1,234,000	$ 232,000
Beginning balance, shares at Sep. 30, 2023				12,338,845	2,318,857
Net Income (Loss)	13,106,000
Ending balance at Jun. 30, 2024	194,689,000	12,590,000	180,633,000	$ 1,234,000	$ 232,000
Ending balance, shares at Jun. 30, 2024				12,338,845	2,318,857
Beginning balance at Dec. 31, 2023	185,909,000	12,590,000	171,853,000	$ 1,234,000	$ 232,000
Beginning balance, shares at Dec. 31, 2023				12,338,845	2,318,857
Net Income (Loss)	6,222,000		6,222,000
Ending balance at Mar. 31, 2024	192,131,000	12,590,000	178,075,000	$ 1,234,000	$ 232,000
Ending balance, shares at Mar. 31, 2024				12,338,845	2,318,857
Net Income (Loss)	2,558,000		2,558,000
Ending balance at Jun. 30, 2024	$ 194,689,000	$ 12,590,000	$ 180,633,000	$ 1,234,000	$ 232,000
Ending balance, shares at Jun. 30, 2024				12,338,845	2,318,857