Investments (Schedule of Amortized Cost, Unrealized Gains and Losses, and Market Value of Investment Securities) (Details) - USD ($)	Mar. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Cost	$ 176,760,632	$ 172,587,805
Unrealized Gains	337,710	236,375
Unrealized Losses	(10,554,281)	(13,034,062)
Market Value	166,544,061	159,790,118
Short-Term Investments \| Certificate of Deposit
Debt Securities, Available-for-sale [Line Items]
Cost	1,750,000	1,750,256
Unrealized Gains	93	0
Unrealized Losses	(8,798)	(14,093)
Market Value	1,741,295	1,736,163
Short-Term Investments \| Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	5,542,607	5,571,417
Unrealized Gains	0	0
Unrealized Losses	(47,497)	(98,076)
Market Value	5,495,110	5,473,341
Short-Term Investments \| Government Securities
Debt Securities, Available-for-sale [Line Items]
Cost	6,190,793	4,476,613
Unrealized Gains	2,058	0
Unrealized Losses	(37,628)	(53,572)
Market Value	6,155,223
Short-Term Investments \| Municipal Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	3,998,537	5,223,500
Unrealized Gains	0	0
Unrealized Losses	(34,552)	(48,727)
Market Value	3,963,985
Short-Term Investments \| Other
Debt Securities, Available-for-sale [Line Items]
Cost	4,474,175	2,347,602
Unrealized Gains	0	0
Unrealized Losses	0	0
Market Value	4,474,175	2,347,602
Long-Term Investments \| Asset Backed Securities
Debt Securities, Available-for-sale [Line Items]
Cost	18,852,424	19,151,229
Unrealized Gains	0	0
Unrealized Losses	(134,166)	(321,533)
Market Value	18,718,258	18,829,696
Long-Term Investments \| Certificate of Deposit
Debt Securities, Available-for-sale [Line Items]
Cost	250,000	250,000
Unrealized Gains	0	0
Unrealized Losses	(10,893)	(11,075)
Market Value	239,107	238,925
Long-Term Investments \| Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	40,819,361	40,410,206
Unrealized Gains	20,678	0
Unrealized Losses	(3,597,540)	(4,099,729)
Market Value	37,242,499	36,310,477
Long-Term Investments \| Government Securities
Debt Securities, Available-for-sale [Line Items]
Cost	39,525,976	39,637,461
Unrealized Gains	0	0
Unrealized Losses	(2,603,327)	(3,104,827)
Market Value	36,922,649	36,532,634
Long-Term Investments \| Municipal Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	54,635,848	53,476,883
Unrealized Gains	314,881	235,713
Unrealized Losses	(4,079,880)	(5,282,430)
Market Value	50,870,849	48,430,166
Long-Term Investments \| Common Stock
Debt Securities, Available-for-sale [Line Items]
Cost	720,911	292,638
Unrealized Gains	0	662
Unrealized Losses	0	0
Market Value	$ 720,911	$ 293,300

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 45
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-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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