Unaudited Condensed Consolidated Statements of Shareholders' Investment - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023		Jun. 30, 2022
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	$ 2,123,255,648	$ 1,928,968,900	$ 2,065,792,821	[1]	$ 1,937,988,467
Issuance of common stock from stock plan transactions	7,926,787	5,671,020	$ 13,882,810		8,995,167
Issuance of common stock related to acquisitions		5,000,012			5,000,012
Repurchases of common stock (in shares)			(2,000,000)
Repurchases of common stock	(25,103,491)	0	$ (53,566,122)		(71,252,022)
Stock-based compensation expense related to stock options, employee stock purchases and restricted stock	9,744,670	8,573,230	18,264,205		15,361,567
Dividends declared	(28,011,420)	(28,214,614)	(56,058,218)		(56,568,616)
Net income	109,155,403	72,404,403	206,733,664		159,933,028
Other comprehensive (loss) income	(1,018,271)	(5,828,471)	900,166		(12,883,123)
Balance at end of period	$ 2,195,949,326	$ 1,986,574,480	$ 2,195,949,326		$ 1,986,574,480
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance (in shares)	233,726,045	234,477,338	234,169,335		236,440,840
Balance at beginning of period	$ 14,023,563	$ 14,068,640	$ 14,050,160		$ 14,186,450
Issuance of common stock from stock plan transactions (in shares)	624,323	492,494	1,227,959		969,182
Issuance of common stock from stock plan transactions	$ 37,459	$ 29,550	$ 73,677		$ 58,151
Issuance of common stock related to acquisitions (in shares)		162,433			162,433
Issuance of common stock related to acquisitions		$ 9,746			$ 9,746
Repurchases of common stock (in shares)	(920,374)	0	(1,967,300)		(2,440,190)
Repurchases of common stock	$ (55,223)	$ 0	$ (118,038)		$ (146,411)
Ending balance (in shares)	233,429,994	235,132,265	233,429,994		235,132,265
Balance at end of period	$ 14,005,799	$ 14,107,936	$ 14,005,799		$ 14,107,936
Additional  Paid-In Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	928,284,892	881,371,438	917,499,323		879,413,385
Issuance of common stock from stock plan transactions	7,889,328	5,641,470	13,809,133		8,937,016
Issuance of common stock related to acquisitions		4,990,266			4,990,266
Repurchases of common stock	(3,258,126)	0	(6,911,897)		(8,125,830)
Stock-based compensation expense related to stock options, employee stock purchases and restricted stock	9,744,670	8,573,230	18,264,205		15,361,567
Balance at end of period	942,660,764	900,576,404	942,660,764		900,576,404
Retained  Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	1,193,171,690	1,038,656,230	1,148,386,272		1,042,461,388
Repurchases of common stock	(21,790,142)	0	(46,536,187)		(62,979,781)
Dividends declared	(28,011,420)	(28,214,614)	(56,058,218)		(56,568,616)
Net income	109,155,403	72,404,403	206,733,664		159,933,028
Balance at end of period	1,252,525,531	1,082,846,019	1,252,525,531		1,082,846,019
Accumulated  Other Comprehensive Loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	(12,224,497)	(5,127,408)	(14,142,934)		1,927,244
Other comprehensive (loss) income	(1,018,271)	(5,828,471)	900,166		(12,883,123)
Balance at end of period	$ (13,242,768)	$ (10,955,879)	$ (13,242,768)		$ (10,955,879)

[1] The condensed consolidated balance sheet at December 31, 2022 has been derived from the audited consolidated financial statements at that date, but does not include all of the information and footnotes required by accounting principles generally accepted in the United States for complete financial statements.