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Summary of Significant Accounting and Reporting Policies (Schedule of Assets or Liabilities Having Recurring Measurements) (Details) (USD $) | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
--- | --- | --- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash & Cash Equivalents | $ 309,591,724 | $ 389,678,664 |  |
Cash and cash equivalents | 309,591,724 | 389,678,664 | 357,986,774 | 348,349,773
Total | 416,597,246 | 592,315,554 |  |
Certificate of Deposit |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 510,881 |  |
Government Securities |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 38,522,471 |  |
U.S. Treasury Notes |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 15,020,350 |  |
Corporate Bonds |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 6,563,228 |  |
Long-Term Investments |  | 2,180,780 |  |
Other |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 185,926 |  |
Common Stocks |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Long-Term Investments | 33,282,439 | 53,283,201 |  |
Mutual Funds – Equity |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Long-Term Investments | 73,723,083 | 86,109,053 |  |
Other – Equity |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Long-Term Investments |  | 261,000 |  |
Level 1 |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash & Cash Equivalents |  | 389,678,664 |  |
Cash and cash equivalents | 309,591,724 |  |  |
Total | 416,597,246 | 529,517,844 |  |
Level 1 | Certificate of Deposit |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 0 |  |
Level 1 | Government Securities |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 0 |  |
Level 1 | U.S. Treasury Notes |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 0 |  |
Level 1 | Corporate Bonds |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 0 |  |
Long-Term Investments |  | 0 |  |
Level 1 | Other |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 185,926 |  |
Level 1 | Common Stocks |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Long-Term Investments | 33,282,439 | 53,283,201 |  |
Level 1 | Mutual Funds – Equity |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Long-Term Investments | 73,723,083 | 86,109,053 |  |
Level 1 | Other – Equity |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Long-Term Investments |  | 261,000 |  |
Level 2 |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash & Cash Equivalents | 0 | 0 |  |
Total | 0 | 62,797,710 |  |
Level 2 | Certificate of Deposit |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 510,881 |  |
Level 2 | Government Securities |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 38,522,471 |  |
Level 2 | U.S. Treasury Notes |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 15,020,350 |  |
Level 2 | Corporate Bonds |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 6,563,228 |  |
Long-Term Investments |  | 2,180,780 |  |
Level 2 | Other |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 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 – Equity |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Long-Term Investments | 0 | 0 |  |
Level 2 | Other – Equity |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Long-Term Investments |  | 0 |  |
Level 3 |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Cash & Cash Equivalents | 0 | 0 |  |
Total |  |  |  |
Level 3 | Certificate 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 |  |
Level 3 | U.S. Treasury Notes |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 0 |  |
Level 3 | Corporate Bonds |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 0 |  |
Long-Term Investments |  | 0 |  |
Level 3 | Other |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Short-Term Investments |  | 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 – Equity |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Long-Term Investments | 0 | 0 |  |
Level 3 | Other – Equity |  |  |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |  |  |
Long-Term Investments |  | $ 0 |  |

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