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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

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- Definition 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). + References 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 + Details
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