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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, 2018 | Dec. 31, 2017
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Cost | $ 303,467,531 | $ 196,926,043
Unrealized Gains | 440,807 | 10,562,267
Unrealized Losses | (366,257) | (367,837)
Market Value | 303,542,081 | 207,120,473
Certificates of Deposit |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 150,299,384 | 130,000,000
Unrealized Gains | 0 | 0
Unrealized Losses | 0 | 0
Market Value | 150,299,384 | 130,000,000
Government Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 9,186,586 | 9,024,777
Unrealized Gains | 0 | 0
Unrealized Losses | (10,359) | (13,647)
Market Value | 9,176,227 | 9,011,130
Municipal Bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 17,840,518 |
Unrealized Gains | 184,914 |
Unrealized Losses | 0 |
Market Value | 18,025,432 |
Mutual Funds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost |  | 392,482
Unrealized Gains |  | 1,575
Unrealized Losses |  | (476)
Market Value |  | 393,581
Corporate Bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 6,981,305 | 12,952,229
Unrealized Gains | 0 | 0
Unrealized Losses | (13,605) | (7,230)
Market Value | 6,967,700 | 12,944,999
Other |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 2,219,688 | 188,344
Unrealized Gains | 0 | 0
Unrealized Losses | 0 | 0
Market Value | 2,219,688 | 188,344
Corporate Bonds |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 60,659,498 | 3,022,994
Unrealized Gains | 50,340 | 0
Unrealized Losses | (339,908) | (4,274)
Market Value | 60,369,930 | 3,018,720
Common Stocks |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 0 | 10,897,219
Unrealized Gains | 0 | 5,079,815
Unrealized Losses | 0 | (273,663)
Market Value | 0 | 15,703,371
Mutual Funds – Equity |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost |  | 29,306,540
Unrealized Gains |  | 5,440,344
Unrealized Losses |  | (65,547)
Market Value |  | 34,681,337
Preferred Stock |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost |  | 1,141,458
Unrealized Gains |  | 40,533
Unrealized Losses |  | (3,000)
Market Value |  | $ 1,178,991
Government Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 56,280,552 |
Unrealized Gains | 205,553 |
Unrealized Losses | (2,385) |
Market Value | 56,483,720 |
Government Securities |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost | 0 |
Unrealized Gains | 0 |
Unrealized Losses | 0 |
Market Value | $ 0 |

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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 http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563 + Details
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