Investments in Securities and Fair Value Schedule of Gross Unrealized Gains and Losses and Amortized Cost for Securities (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Available-for-sale Securities [Abstract]
Amortized Cost	$ 104,421,050	$ 87,980,160
Gross Unrealized Gains	4,773,623	3,962,860
Gross Unrealized Losses	146,383	497,607
Estimated Fair Value	109,048,290us-gaap_AvailableForSaleSecurities	91,445,413us-gaap_AvailableForSaleSecurities
Amortized Cost	24,128,753	22,200,369
Gross Unrealized Gains	15,225,459	14,052,780
Gross Unrealized Losses	99,231	109,084
Estimated Fair Value	39,254,981	36,144,065
Short Term Investments Amortized Cost Basis	2,576,993	7,926,373
Short Term Investments Gross Unrealized Gains	0	0
Short Term Investments Gross Unrealized Losses	0	0
Short Term Investments Estimated Fair Value	2,576,993	7,926,373
General obligations of U.S. states, territories and political subdivisions
Available-for-sale Securities [Abstract]
Amortized Cost	35,215,247	38,449,309
Gross Unrealized Gains	1,527,794	1,922,862
Gross Unrealized Losses	19,542	184,351
Estimated Fair Value	36,723,499	40,187,820
Issuer obligations of U.S. states, territories and political subdivisions special revenue
Schedule of Trading Securities and Other Trading Assets [Line Items]
Number of Special Revenue Bonds	30
Available-for-sale Securities [Abstract]
Amortized Cost	46,707,033	30,874,571
Gross Unrealized Gains	2,405,725	1,234,130
Gross Unrealized Losses	55,502	204,800
Estimated Fair Value	49,057,256	31,903,901
Corporate debt securities
Available-for-sale Securities [Abstract]
Amortized Cost	21,576,641	17,736,608
Gross Unrealized Gains	823,133	789,840
Gross Unrealized Losses	71,339	108,456
Estimated Fair Value	22,328,435	18,417,992
Auction rate securities
Available-for-sale Securities [Abstract]
Amortized Cost	922,129	919,672
Gross Unrealized Gains	16,971	16,028
Gross Unrealized Losses	0	0
Estimated Fair Value	939,100	935,700
Common stocks and nonredeemable preferred stocks
Available-for-sale Securities [Abstract]
Amortized Cost	24,128,753	22,200,369
Gross Unrealized Gains	15,225,459	14,052,780
Gross Unrealized Losses	99,231	109,084
Estimated Fair Value	39,254,981	36,144,065
Money market funds and certificates of deposit
Available-for-sale Securities [Abstract]
Short Term Investments Amortized Cost Basis	2,576,993	7,926,373
Short Term Investments Gross Unrealized Gains	0	0
Short Term Investments Gross Unrealized Losses	0	0
Short Term Investments Estimated Fair Value	$ 2,576,993	$ 7,926,373

Available-For-Sale Equity Securities Estimated Fair Value

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Available-For-Sale Equity Securities Gross Unrealized Gains

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Available-For-Sale Equity Securities Gross Unrealized Losses

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Amount of accumulated pre-tax unrealized gains before deducting pre-tax unrealized losses on investments in available-for-sale securities impacting investments.

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Amount of accumulated pre-tax unrealized loss before deducting pre-tax unrealized gain on investments in available-for-sale securities impacting investments.

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Number of Special Revenue Bonds

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Short Term Investments Amortized Cost Basis

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Short Term Investments Estimated Fair Value

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This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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