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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

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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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