Unaudited Condensed Consolidated Statements of Shareholders Equity - USD ($)	Common stock	Treasury Stock	Additional paid-in capital	Retained Earnings	Total
Balance - beginning at Mar. 31, 2022	$ 513,217	$ (121,226,936)	$ 760,105,994	$ 280,759,140	$ 920,151,415
Balance - beginning (Shares) at Mar. 31, 2022	51,321,695
Increase (Decrease) in Shareholders' Equity
Net income for the period				24,847,720	24,847,720
Restricted share award issuances	$ 158		(158)
Restricted share award issuances (Shares)	15,750
Dividend ($2.50 per common share)				(100,337,605)	(100,337,605)
Stock-based compensation			658,872		658,872
Purchase of treasury stock		(971,067)			(971,067)
Balance - Ending at Jun. 30, 2022	$ 513,375	(122,198,003)	760,764,708	205,269,255	844,349,335
Balance - ending (Shares) at Jun. 30, 2022	51,337,445
Balance - beginning at Mar. 31, 2022	$ 513,217	(121,226,936)	760,105,994	280,759,140	920,151,415
Balance - beginning (Shares) at Mar. 31, 2022	51,321,695
Increase (Decrease) in Shareholders' Equity
Net income for the period					96,422,895
Balance - Ending at Dec. 31, 2022	$ 515,960	(122,896,838)	763,547,096	196,161,062	837,327,280
Balance - ending (Shares) at Dec. 31, 2022	51,595,898
Balance - beginning at Jun. 30, 2022	$ 513,375	(122,198,003)	760,764,708	205,269,255	844,349,335
Balance - beginning (Shares) at Jun. 30, 2022	51,337,445
Increase (Decrease) in Shareholders' Equity
Net income for the period				20,311,465	20,311,465
Restricted share award issuances	$ 2,408		(2,408)
Restricted share award issuances (Shares)	240,751
Dividend ($1.00 per common share)				(40,332,833)	(40,332,833)
Stock-based compensation			1,740,328		1,740,328
Purchase of treasury stock		(698,835)			(698,835)
Balance - Ending at Sep. 30, 2022	$ 515,783	(122,896,838)	762,502,628	185,247,887	825,369,460
Balance - ending (Shares) at Sep. 30, 2022	51,578,196
Increase (Decrease) in Shareholders' Equity
Net income for the period				51,263,710	51,263,710
Restricted share award issuances	$ 177		(177)
Restricted share award issuances (Shares)	17,702
Dividend ($1.00 per common share)				(40,350,535)	(40,350,535)
Stock-based compensation			1,044,645		1,044,645
Balance - Ending at Dec. 31, 2022	$ 515,960	(122,896,838)	763,547,096	196,161,062	837,327,280
Balance - ending (Shares) at Dec. 31, 2022	51,595,898
Balance - beginning at Mar. 31, 2023	$ 516,306	(122,896,838)	764,383,292	231,843,562	873,846,322
Balance - beginning (Shares) at Mar. 31, 2023	51,630,593
Increase (Decrease) in Shareholders' Equity
Net income for the period				51,721,137	51,721,137
Restricted share award issuances	$ 238		(238)
Restricted share award issuances (Shares)	23,750
Dividend ($1.00 per common share)				(40,382,730)	(40,382,730)
Stock-based compensation			776,607		776,607
Purchase of treasury stock		(352,627)			(352,627)
Balance - Ending at Jun. 30, 2023	$ 516,544	(123,249,465)	765,159,661	243,181,969	885,608,709
Balance - ending (Shares) at Jun. 30, 2023	51,654,343
Balance - beginning at Mar. 31, 2023	$ 516,306	(122,896,838)	764,383,292	231,843,562	873,846,322
Balance - beginning (Shares) at Mar. 31, 2023	51,630,593
Increase (Decrease) in Shareholders' Equity
Net income for the period					228,206,715
Balance - Ending at Dec. 31, 2023	$ 519,554	(125,670,534)	770,720,529	338,488,767	984,058,316
Balance - ending (Shares) at Dec. 31, 2023	51,955,408
Balance - beginning at Jun. 30, 2023	$ 516,544	(123,249,465)	765,159,661	243,181,969	885,608,709
Balance - beginning (Shares) at Jun. 30, 2023	51,654,343
Increase (Decrease) in Shareholders' Equity
Net income for the period				76,512,665	76,512,665
Restricted share award issuances	$ 3,010		(3,010)
Restricted share award issuances (Shares)	301,065
Dividend ($1.00 per common share)				(40,570,888)	(40,570,888)
Stock-based compensation			4,179,798		4,179,798
Purchase of treasury stock		(2,421,069)			(2,421,069)
Balance - Ending at Sep. 30, 2023	$ 519,554	(125,670,534)	769,336,449	279,123,746	923,309,215
Balance - ending (Shares) at Sep. 30, 2023	51,955,408
Increase (Decrease) in Shareholders' Equity
Net income for the period				99,972,913	99,972,913
Dividend ($1.00 per common share)				(40,607,892)	(40,607,892)
Stock-based compensation			1,384,080		1,384,080
Balance - Ending at Dec. 31, 2023	$ 519,554	$ (125,670,534)	$ 770,720,529	$ 338,488,767	$ 984,058,316
Balance - ending (Shares) at Dec. 31, 2023	51,955,408