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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, 2016 | Dec. 31, 2015
--- | --- | ---
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | $ 222,624,828 | $ 98,427,114
Unrealized Gains | 5,209,434 | 6,146,311
Unrealized Losses | (918,703) | (4,869,531)
Market Value | 226,915,559 | 99,703,894
Certificates of Deposit |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 130,000,000 |
Unrealized Gains | 0 |
Unrealized Losses | 0 |
Market Value | 130,000,000 |
Government Securities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 14,003,644 | 3,013,482
Unrealized Gains | 0 | 0
Unrealized Losses | (10,164) | (2,622)
Market Value | 13,993,480 | 3,010,860
Government Securities |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 5,519,668 |
Unrealized Gains | 661 |
Unrealized Losses | (9,539) |
Market Value | 5,510,790 |
Mutual Funds |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 26,326,674 |
Unrealized Gains | 27,459 |
Unrealized Losses | (237,452) |
Market Value | 26,116,681 |
Corporate Bonds |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 6,706,721 | 1,512,405
Unrealized Gains | 0 | 0
Unrealized Losses | (8,339) | (390)
Market Value | 6,698,382 | 1,512,015
Other |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 212,653 | 24,480
Unrealized Gains | 0 | 0
Unrealized Losses | 0 | 0
Market Value | 212,653 | 24,480
Corporate Bond, Long-Term Investments |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 1,955,292 |
Unrealized Gains | 0 |
Unrealized Losses | (6,736) |
Market Value | 1,948,556 |
Common Stocks |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 9,825,550 | 17,395,641
Unrealized Gains | 3,349,962 | 4,078,912
Unrealized Losses | (326,505) | (1,019,749)
Market Value | 12,849,007 | 20,454,804
Mutual Funds – Equity |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 27,329,164 | 76,481,106
Unrealized Gains | 1,830,992 | 2,067,399
Unrealized Losses | (288,146) | (3,846,770)
Market Value | 28,872,010 | $ 74,701,735
Preferred Stock |  |
Schedule of Available-for-sale Securities [Line Items] |  |
Cost | 745,462 |
Unrealized Gains | 360 |
Unrealized Losses | (31,822) |
Market Value | $ 714,000 |

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