Investments (Schedule of Amortized Cost, Unrealized Gains and Losses, and Market Value of Investment Securities) (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Cost	$ 170,677,313	$ 195,025,034
Unrealized Gains	284,003	3,093,114
Unrealized Losses	(6,804,987)	(1,818,868)
Market Value	164,156,329	196,299,280
Short-Term Investments \| Certificate of Deposit
Debt Securities, Available-for-sale [Line Items]
Cost	751,354	1,500,543
Unrealized Gains	2,600	7,227
Unrealized Losses	(329)
Market Value	753,625	1,507,770
Short-Term Investments \| Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	1,996,774	1,994,639
Unrealized Gains	5,086	23,801
Unrealized Losses	0	0
Market Value	2,001,860	2,018,440
Short-Term Investments \| Government Securities
Debt Securities, Available-for-sale [Line Items]
Cost
Unrealized Gains
Unrealized Losses		0
Market Value		0
Short-Term Investments \| Municipal Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	1,250,203	0
Unrealized Gains	1,599
Unrealized Losses	0
Market Value	1,251,802	0
Short-Term Investments \| Other
Debt Securities, Available-for-sale [Line Items]
Cost	2,884,333	1,897,402
Unrealized Gains	0
Unrealized Losses	0
Market Value	2,884,333	1,897,402
Long-Term Investments \| Asset Backed Securities
Debt Securities, Available-for-sale [Line Items]
Cost	25,406,929	26,352,630
Unrealized Gains	0	34,771
Unrealized Losses	(625,657)	(587,888)
Market Value	24,781,272	25,799,513
Long-Term Investments \| Certificate of Deposit
Debt Securities, Available-for-sale [Line Items]
Cost	1,750,000	2,001,714
Unrealized Gains	19,888	54,996
Unrealized Losses	(2,650)	0
Market Value	1,767,238	2,056,710
Long-Term Investments \| Corporate Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	43,589,074	40,716,866
Unrealized Gains	0	168,416
Unrealized Losses	(2,411,962)	(530,353)
Market Value	41,177,112	40,354,929
Long-Term Investments \| Government Securities
Debt Securities, Available-for-sale [Line Items]
Cost	40,547,178	48,385,672
Unrealized Gains	0	55,939
Unrealized Losses	(1,861,670)	(497,575)
Market Value	38,685,508	47,944,036
Long-Term Investments \| Municipal Bonds
Debt Securities, Available-for-sale [Line Items]
Cost	52,501,468	72,175,568
Unrealized Gains	254,830	2,747,964
Unrealized Losses	(1,902,719)	(203,052)
Market Value	$ 50,853,579	$ 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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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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), classified as current.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
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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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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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