CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($)	Total	Cumulative Effect, Period of Adoption, Adjustment	Common Stock	Additional Paid-in Capital	Retained Earnings	Retained Earnings Cumulative Effect, Period of Adoption, Adjustment
Beginning balance (in shares) at Mar. 31, 2020			7,807,834
Beginning balances at Mar. 31, 2020	$ 411,963,067	$ (21,242,249)		$ 227,214,577	$ 184,748,490	$ (21,242,249)
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Proceeds from exercise of stock options (in shares)			15,571
Proceeds from exercise of stock options	1,006,825			1,006,825
Common stock repurchases (in shares)			(786,418)
Common stock repurchases	(62,686,925)				(62,686,925)
Restricted common stock expense under stock option plan (in shares)			34,907
Restricted common stock expense under stock option plan	7,193,190			7,193,190
Stock option expense	2,132,974			2,132,974
Net income	28,908,269				28,908,269
Ending balance (in shares) at Sep. 30, 2020			7,002,080
Ending balances at Sep. 30, 2020	367,275,151			237,547,566	129,727,585
Beginning balance (in shares) at Jun. 30, 2020			7,451,588
Beginning balances at Jun. 30, 2020	391,242,915			231,678,312	159,564,603
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Proceeds from exercise of stock options (in shares)			15,571
Proceeds from exercise of stock options	1,006,825			1,006,825
Common stock repurchases (in shares)			(460,120)
Common stock repurchases	(43,235,638)				(43,235,638)
Restricted common stock expense under stock option plan (in shares)			(4,959)
Restricted common stock expense under stock option plan	3,776,190			3,776,190
Stock option expense	1,086,239			1,086,239
Net income	13,398,620				13,398,620
Ending balance (in shares) at Sep. 30, 2020			7,002,080
Ending balances at Sep. 30, 2020	367,275,151			237,547,566	129,727,585
Beginning balance (in shares) at Mar. 31, 2021			6,805,294
Beginning balances at Mar. 31, 2021	404,927,441			255,590,674	149,336,767
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Proceeds from exercise of stock options (in shares)			111,122
Proceeds from exercise of stock options	8,682,578			8,682,578
Common stock repurchases (in shares)			(195,436)
Common stock repurchases	(31,112,523)				(31,112,523)
Restricted common stock expense under stock option plan (in shares)			3,160
Restricted common stock expense under stock option plan	6,445,948			6,445,948
Stock option expense	1,852,977			1,852,977
Net income	28,210,920				28,210,920
Ending balance (in shares) at Sep. 30, 2021			6,724,140
Ending balances at Sep. 30, 2021	419,007,341			272,572,177	146,435,164
Beginning balance (in shares) at Jun. 30, 2021			6,693,703
Beginning balances at Jun. 30, 2021	405,470,862			261,446,129	144,024,733
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Proceeds from exercise of stock options (in shares)			87,628
Proceeds from exercise of stock options	6,873,724			6,873,724
Common stock repurchases (in shares)			(61,187)
Common stock repurchases	(10,029,661)				(10,029,661)
Restricted common stock expense under stock option plan (in shares)			3,996
Restricted common stock expense under stock option plan	3,342,974			3,342,974
Stock option expense	909,350			909,350
Net income	12,440,092				12,440,092
Ending balance (in shares) at Sep. 30, 2021			6,724,140
Ending balances at Sep. 30, 2021	$ 419,007,341			$ 272,572,177	$ 146,435,164