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Investments - Schedule of Amortized Cost, Unrealized Gains and Losses, and Market Value of Investment Securities (Details) - USD ($) | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Cost | $ 87,200,244 | $ 207,829,040
Unrealized Gains | 2,117,476 | 8,722,554
Unrealized Losses | (342,024) | (10,543,405)
Market Value | 88,975,696 | 206,008,189
Short-Term Investments | Asset-backed Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost |  | 2,834,713
Unrealized Gains |  | 17,220
Unrealized Losses |  | 0
Market Value |  | 2,851,933
Short-Term Investments | Certificate of Deposit |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost |  | 750,000
Unrealized Gains |  | 1,728
Unrealized Losses |  | 0
Market Value |  | 751,728
Short-Term Investments | Corporate Bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 2,251,999 | 4,013,735
Unrealized Gains | 9,854 | 0
Unrealized Losses | 0 | (42,535)
Market Value | 2,261,853 | 3,971,200
Short-Term Investments | Government Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost |  | 3,981,161
Unrealized Gains |  | 1,114
Unrealized Losses |  | 0
Market Value |  | 3,982,275
Short-Term Investments | Municipal Bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost |  | 3,400,019
Unrealized Gains |  | 472
Unrealized Losses |  | (13,991)
Market Value |  | 3,386,500
Short-Term Investments | Other |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 838,907 | 1,400,176
Unrealized Gains | 0 | 0
Unrealized Losses | 0 | 0
Market Value | 838,907 | 1,400,176
Long-Term Investments | Asset-backed Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 29,764,908 | 41,372,112
Unrealized Gains | 1,039,037 | 620,756
Unrealized Losses | 0 | (226,764)
Market Value | 30,803,945 | 41,766,104
Long-Term Investments | Corporate Bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 37,702,921 | 54,552,964
Unrealized Gains | 718,334 | 355,627
Unrealized Losses | (151,942) | (371,074)
Market Value | 38,269,313 | 54,537,517
Long-Term Investments | Government Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost |  | 6,206,437
Unrealized Gains |  | 13,124
Unrealized Losses |  | (20,026)
Market Value |  | 6,199,535
Long-Term Investments | Municipal Bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 16,641,509 | 40,542,837
Unrealized Gains | 350,251 | 209,564
Unrealized Losses | (190,082) | (1,294,083)
Market Value | $ 16,801,678 | 39,458,318
Long-Term Investments | VOXX Common Stock | VOXX Common Stock |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost |  | 48,774,886
Unrealized Gains |  | 7,502,949
Unrealized Losses |  | (8,574,932)
Market Value |  | $ 47,702,903

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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://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481800/320-10-50-2 + Details
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