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Summary of Significant Accounting and Reporting Policies (Schedule of Amortized Cost, Unrealized Gains and Losses, and Market Value of Investment Securities) (Details) - USD ($) | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Cost | $ 172,587,805 | $ 195,025,034
Unrealized gains | 236,375 | 3,093,114
Unrealized losses | (13,034,062) | (1,818,868)
Market Value | 159,790,118 | 196,299,280
Long-term Investments | Common Stock |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 292,638 |
Unrealized gains | 662 |
Unrealized losses | 0 |
Market Value | 293,300 |
Certificate of Deposit | Short-term Investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 1,750,256 | 1,500,543
Unrealized gains | 0 | 7,227
Unrealized losses | (14,093) | 0
Market Value | 1,736,163 | 1,507,770
Certificate of Deposit | Long-term Investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 250,000 | 2,001,714
Unrealized gains | 0 | 54,996
Unrealized losses | (11,075) | 0
Market Value | 238,925 | 2,056,710
Asset-backed Securities | Long-term Investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 19,151,229 | 26,352,630
Unrealized gains | 0 | 34,771
Unrealized losses | (321,533) | (587,888)
Market Value | 18,829,696 | 25,799,513
Corporate Bonds | Short-term Investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 5,571,417 | 1,994,639
Unrealized gains | 0 | 23,801
Unrealized losses | (98,076) | 0
Market Value | 5,473,341 | 2,018,440
Corporate Bonds | Long-term Investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 40,410,206 | 40,716,866
Unrealized gains | 0 | 168,416
Unrealized losses | (4,099,729) | (530,353)
Market Value | 36,310,477 | 40,354,929
Government Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost |  | 48,385,672
Unrealized gains |  | 55,939
Unrealized losses |  | (497,575)
Market Value |  | 47,944,036
Government Securities | Short-term Investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 4,476,613 |
Unrealized gains | 0 |
Unrealized losses | (53,572) |
Market Value | 4,423,041 |
Government Securities | Long-term Investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 39,637,461 |
Unrealized gains | 0 |
Unrealized losses | (3,104,827) |
Market Value | 36,532,634 |
Municipal Bonds | Short-term Investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 5,223,500 |
Unrealized gains | 0 |
Unrealized losses | (48,727) |
Market Value | 5,174,773 |
Municipal Bonds | Long-term Investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 53,476,883 | 72,175,568
Unrealized gains | 235,713 | 2,747,964
Unrealized losses | (5,282,430) | (203,052)
Market Value | 48,430,166 | 74,720,480
Other | Short-term Investments |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 2,347,602 | 1,897,402
Unrealized gains | 0 | 0
Unrealized losses | 0 | 0
Market Value | $ 2,347,602 | $ 1,897,402

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