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Summary of Significant Accounting and Reporting Policies (Schedule of Assets or Liabilities Having Recurring Measurements) (Details) - USD ($) | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash & Cash Equivalents | $ 546,477,075 | $ 551,557,527
Total | 773,392,634 | 651,261,421
Certificates of Deposit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 130,000,000 |
Government Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 13,993,480 | 3,010,860
Long-Term Investments | 5,510,790 |
Corporate Bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 6,698,382 | 1,512,015
Long-Term Investments | 1,948,556 |
Other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 212,653 | 24,480
Common Stocks |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Long-Term Investments | 12,849,007 | 20,454,804
Mutual Funds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 26,116,681 |
Mutual Funds – Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Long-Term Investments | 28,872,010 | 74,701,735
Preferred Stock |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Long-Term Investments | 714,000 |
Level 1 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash & Cash Equivalents | 546,477,075 | 551,557,527
Total | 719,124,745 | 646,738,546
Level 1 | Certificates of Deposit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 130,000,000 |
Level 1 | Government Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 0 | 0
Long-Term Investments |  |
Level 1 | Corporate Bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 0 | 0
Long-Term Investments |  |
Level 1 | Other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 212,653 | 24,480
Level 1 | Common Stocks |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Long-Term Investments | 12,849,007 | 20,454,804
Level 1 | Mutual Funds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments |  |
Level 1 | Mutual Funds – Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Long-Term Investments | 28,872,010 | 74,701,735
Level 1 | Preferred Stock |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Long-Term Investments | 714,000 |
Level 2 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash & Cash Equivalents | 0 | 0
Total | 54,267,889 | 4,522,875
Level 2 | Certificates of Deposit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 0 |
Level 2 | Government Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 13,993,480 | 3,010,860
Long-Term Investments | 5,510,790 |
Level 2 | Corporate Bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 6,698,382 | 1,512,015
Long-Term Investments | 1,948,556 |
Level 2 | Other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 0 | 0
Level 2 | Common Stocks |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Long-Term Investments | 0 | 0
Level 2 | Mutual Funds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 26,116,681 |
Level 2 | Mutual Funds – Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Long-Term Investments | 0 | 0
Level 2 | Preferred Stock |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Long-Term Investments |  |
Level 3 |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Cash & Cash Equivalents | 0 | 0
Level 3 | Certificates of Deposit |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 0 |
Level 3 | Government Securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 0 | 0
Long-Term Investments |  |
Level 3 | Corporate Bonds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 0 | 0
Long-Term Investments |  |
Level 3 | Other |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments | 0 | 0
Level 3 | Common Stocks |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Long-Term Investments | 0 | 0
Level 3 | Mutual Funds |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Short-Term Investments |  |
Level 3 | Mutual Funds – Equity |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Long-Term Investments | 0 | $ 0
Level 3 | Preferred Stock |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Long-Term Investments |  |

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