Investments (Schedule of Amortized Cost, Unrealized Gains and Losses, and Market Value of Investment Securities) (Details) - USD ($)	Sep. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Cost	$ 170,850,381	$ 195,025,034
Unrealized Gains	186,625	3,093,114
Unrealized Losses	(14,564,460)	(1,818,868)
Market Value	156,472,546	196,299,280
Short-Term Investments \| Certificate of Deposit
Debt Securities, Available-for-sale [Line Items]
Cost	1,750,623	1,500,543
Unrealized Gains	0	7,227
Unrealized Losses	(18,076)	0
Market Value	1,732,547	1,507,770
Short-Term Investments \| Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	5,600,869	1,994,639
Unrealized Gains	0	23,801
Unrealized Losses	(154,821)	0
Market Value	5,446,048	2,018,440
Short-Term Investments \| Government Securities
Debt Securities, Available-for-sale [Line Items]
Cost	2,211,230
Unrealized Gains	0
Unrealized Losses	(1,899)
Market Value	2,209,331
Short-Term Investments \| Municipal Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	3,549,066
Unrealized Gains	0
Unrealized Losses	(39,378)
Market Value	3,509,688
Short-Term Investments \| Other
Debt Securities, Available-for-sale [Line Items]
Cost	1,230,180	1,897,402
Unrealized Gains	0	0
Unrealized Losses	0	0
Market Value	1,230,180	1,897,402
Long-Term Investments \| Asset Backed Securities
Debt Securities, Available-for-sale [Line Items]
Cost	21,716,039	26,352,630
Unrealized Gains	0	34,771
Unrealized Losses	(773,180)	(587,888)
Market Value	20,942,859	25,799,513
Long-Term Investments \| Certificate of Deposit
Debt Securities, Available-for-sale [Line Items]
Cost	250,000	2,001,714
Unrealized Gains	0	54,996
Unrealized Losses	(11,207)	0
Market Value	238,793	2,056,710
Long-Term Investments \| Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	39,223,627	40,716,866
Unrealized Gains	0	168,416
Unrealized Losses	(4,701,010)	(530,353)
Market Value	34,522,617	40,354,929
Long-Term Investments \| Government Securities
Debt Securities, Available-for-sale [Line Items]
Cost	41,116,603	48,385,672
Unrealized Gains	0	55,939
Unrealized Losses	(3,422,863)	(497,575)
Market Value	37,693,740	47,944,036
Long-Term Investments \| Municipal Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	54,202,144	72,175,568
Unrealized Gains	186,625	2,747,964
Unrealized Losses	(5,442,026)	(203,052)
Market Value	$ 48,946,743	$ 74,720,480

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)
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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
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-Section 45
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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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