Comprehensive Income (AOCI Rollforward) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022		Jun. 30, 2021	Dec. 31, 2021	[1]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	$ 1,928,968,900	$ 1,960,980,714	$ 1,937,988,467	[1]	$ 1,963,943,128
Net current-period change	(5,828,471)	2,310,371	(12,883,123)		(2,586,014)
Balance at end of period	1,986,574,480	1,916,318,989	1,986,574,480		1,916,318,989
Accumulated other comprehensive (loss) income, end of period	(10,955,879)		(10,955,879)			$ 1,927,244
Accumulated  Other Comprehensive (Loss) Income
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(5,127,408)	1,954,667	1,927,244		6,851,052
Net current-period change	(5,828,471)	2,310,371	(12,883,123)		(2,586,014)
Balance at end of period	(10,955,879)	4,265,038	(10,955,879)		4,265,038
Accumulated other comprehensive (loss) income, end of period	(10,955,879)	4,265,038	(10,955,879)		4,265,038
Foreign currency translation adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	24,169	(83,367)	920,589		769,045
Other Comprehensive (loss) income before reclassifications	(3,131,326)	963,199	(4,027,746)		110,787
Net current-period change	(3,131,326)	963,199	(4,027,746)		110,787
Balance at end of period	(3,107,157)	879,832	(3,107,157)		879,832
Unrealized gains on available-for-sale debt securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at beginning of period	(5,151,577)	2,038,034	1,006,655		6,082,007
Other Comprehensive (loss) income before reclassifications	(2,903,717)	1,610,141	(9,327,653)		(2,082,477)
Amounts reclassified from accumulated other comprehensive income	206,572	(262,969)	472,276		(614,324)
Net current-period change	(2,697,145)	1,347,172	(8,855,377)		(2,696,801)
Balance at end of period	$ (7,848,722)	$ 3,385,206	$ (7,848,722)		$ 3,385,206

[1] The condensed consolidated balance sheet at December 31, 2021 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.