CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Unaudited) - USD ($)	Total	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Employee Stock Option [Member]
Common Stock, Shares, Outstanding	9,284,118
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	39,766
Balances at Mar. 31, 2019	$ 552,116,625	$ 198,125,649	$ 353,990,976
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Proceeds from exercise of stock options, including tax benefits	$ 2,676,573
Stock Repurchased and Retired During Period, Shares	(141,077)
Stock Repurchased and Retired During Period, Value			(21,815,577)
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures	(1,502)
Issuance of restricted common stock under stock option plan	$ 6,452,703	6,452,703
Stock option expense	1,621,338	1,621,338
Net income	8,608,399		8,608,399
Balances at Jun. 30, 2019	$ 549,660,061	208,876,263	340,783,798
Common Stock, Shares, Outstanding	9,181,305
Common Stock, Shares, Outstanding	7,807,834
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	0			0
Balances at Mar. 31, 2020	$ 411,963,067	227,214,577	184,748,490
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Proceeds from exercise of stock options, including tax benefits	$ 0
Stock Repurchased and Retired During Period, Shares	(326,298)
Stock Repurchased and Retired During Period, Value			(19,451,287)
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures	(29,948)
Issuance of restricted common stock under stock option plan	$ 3,417,000	3,417,000
Stock option expense	1,046,735	1,046,735
Net income	15,509,649		15,509,649
Balances at Jun. 30, 2020	$ 391,242,915	$ 231,678,312	$ 159,564,603
Common Stock, Shares, Outstanding	7,451,588
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Cumulative Effect of New Accounting Principle in Period of Adoption	$ 21,242,249