Other Investments (Schedule of Other Investments) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2019
Other Assets:
Investment in unconsolidated affiliates	$ 52,291,160		$ 52,291,160		$ 47,375,459
Current Liabilities:
Capital contributions payable	1,726,786		1,726,786		5,024,824
Income Statement location of Other Investments:
Equity in earnings of unconsolidated affiliate	1,188,593	$ 698,175	2,282,679	$ 1,261,224
Undistributed earnings, net of income taxes, of MVP in retained earnings	4,962,293		4,962,293		3,267,176
Change in investment in unconsolidated affiliate [Abstract]
Cash investment			5,931,060	13,304,263
Change in accrued capital calls			(3,298,038)	(6,796,085)
Equity in earnings of unconsolidated affiliate	1,188,593	$ 698,175	2,282,679	1,261,224
Change in investment in unconsolidated affiliates			4,915,701	$ 7,769,402
MVP [Member]
Other Assets:
MVP	51,971,127		51,971,127		47,055,426
Current Liabilities:
Capital contributions payable	1,726,786		1,726,786		4,958,260
Southgate [Member]
Other Assets:
Southgate	320,033		320,033		320,033
Current Liabilities:
Capital contributions payable	$ 0		$ 0		$ 66,564