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Investments (Schedule of Assets or Liabilities, Recurring Fair Value Measurements) (Details) - USD ($) | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash & Cash Equivalents | $ 215,452,160 | $ 214,754,638
Restricted Cash | 4,000,000 | 4,000,000
Market Value | 166,544,061 | 159,790,118
Total | 385,996,220 | 378,544,756
(Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash & Cash Equivalents | 215,452,160 | 214,754,638
Restricted Cash | 4,000,000 | 4,000,000
Total | 223,160,622 | 222,116,628
(Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash & Cash Equivalents | 0 | 0
Restricted Cash | 0 | 0
Total | 162,835,598 | 156,428,128
(Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash & Cash Equivalents | 0 | 0
Restricted Cash | 0 | 0
Total | 0 | 0
Short-Term Investments | Certificate of Deposit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 1,741,295 | 1,736,163
Short-Term Investments | Certificate of Deposit | (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 1,741,295 | 1,736,163
Short-Term Investments | Certificate of Deposit | (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Short-Term Investments | Certificate of Deposit | (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Short-Term Investments | Corporate Bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 5,495,110 | 5,473,341
Short-Term Investments | Corporate Bonds | (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Short-Term Investments | Corporate Bonds | (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 5,495,110 | 5,473,341
Short-Term Investments | Corporate Bonds | (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Short-Term Investments | Government Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 6,155,223 | 4,423,041
Short-Term Investments | Government Securities | (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Short-Term Investments | Government Securities | (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 6,155,223 | 4,423,041
Short-Term Investments | Government Securities | (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Short-Term Investments | Municipal Bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 3,963,985 | 5,174,773
Short-Term Investments | Municipal Bonds | (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Short-Term Investments | Municipal Bonds | (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 3,963,985 | 5,174,773
Short-Term Investments | Municipal Bonds | (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Short-Term Investments | Other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 4,474,175 | 2,347,602
Short-Term Investments | Other | (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 1,007,150 | 1,093,602
Short-Term Investments | Other | (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 3,467,025 | 1,254,000
Short-Term Investments | Other | (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Long-Term Investments | Asset Backed Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 18,718,258 | 18,829,696
Long-Term Investments | Asset Backed Securities | (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Long-Term Investments | Asset Backed Securities | (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 18,718,258 | 18,829,696
Long-Term Investments | Asset Backed Securities | (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Long-Term Investments | Certificate of Deposit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 239,107 | 238,925
Long-Term Investments | Certificate of Deposit | (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 239,107 | 238,925
Long-Term Investments | Certificate of Deposit | (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Long-Term Investments | Certificate of Deposit | (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Long-Term Investments | Corporate Bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 37,242,499 | 36,310,477
Long-Term Investments | Corporate Bonds | (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Long-Term Investments | Corporate Bonds | (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 37,242,499 | 36,310,477
Long-Term Investments | Corporate Bonds | (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Long-Term Investments | Government Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 36,922,649 | 36,532,634
Long-Term Investments | Government Securities | (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Long-Term Investments | Government Securities | (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 36,922,649 | 36,532,634
Long-Term Investments | Government Securities | (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Long-Term Investments | Municipal Bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 50,870,849 | 48,430,166
Long-Term Investments | Municipal Bonds | (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Long-Term Investments | Municipal Bonds | (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 50,870,849 | 48,430,166
Long-Term Investments | Municipal Bonds | (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 |
Long-Term Investments | Common Stock |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 720,910 | 293,300
Long-Term Investments | Common Stock | (Level 1) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 720,910 | 293,300
Long-Term Investments | Common Stock | (Level 2) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | 0 | 0
Long-Term Investments | Common Stock | (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Market Value | $ 0 | $ 0

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