UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 311,459,076	$ 232,589,023
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	71,001,177	73,289,065
(Gain) on disposal of assets	(271,510)	(56,257)
Loss on disposal of assets	250,435	22,096
(Gain) on sale of investments and equity method investment income	(2,747,586)	(391,378)
Loss on sale of investments and equity method investment losses	6,840,692	1,248,450
Change in deferred income taxes	(11,870,944)	4,785,787
Stock-based compensation expense related to employee stock options, employee stock purchases and restricted stock	29,212,236	22,973,113
Change in operating assets and liabilities:
Accounts receivable, net	(74,648,395)	(42,618,585)
Inventories	8,907,490	(102,018,719)
Prepaid expenses and other	(5,416,624)	(16,978,469)
Accounts payable	27,451,773	52,511,201
Accrued liabilities, excluding dividends declared	7,500,486	11,002,238
Net cash provided by operating activities	367,668,306	236,357,565
Activity in investments:
Sales proceeds	32,839,883	37,429,595
Maturities and calls	14,435,000	3,500,000
Purchases	(112,608,739)	(49,554,476)
Plant and equipment additions	(121,393,801)	(108,475,787)
Proceeds from sale of plant and equipment	185,610	91,949
Increase in other assets	(2,533,687)	(2,310,428)
Net cash used for investing activities	(189,075,734)	(119,319,147)
CASH FLOWS USED FOR FINANCING ACTIVITIES:
Issuance of common stock from stock plan transactions	24,304,861	12,365,103
Cash dividends paid	(84,159,105)	(84,941,178)
Repurchases of common stock	(76,859,341)	(83,840,290)
Net cash used for financing activities	(136,713,585)	(156,416,365)
NET INCREASE IN CASH AND CASH EQUIVALENTS	41,878,987	(39,377,947)
CASH, CASH EQUIVALENTS, and RESTRICTED CASH, beginning of period	218,754,638	262,311,670
CASH, CASH EQUIVALENTS, and RESTRICTED CASH, end of period	260,633,625	222,933,723
Property and equipment in accounts payable and accrued expenses and other current liabilities	$ 9,708,125	$ 5,064,356