Investments - Investment Income (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Notes to Financial Statements
Investment income excluding short term investments	$ 102,471	$ 253,252	$ 1,469,706
Investment Income from short-term investments	59,267	79,745	59,269
Total investment income	$ 161,738us-gaap_InvestmentIncomeInterest	$ 332,997us-gaap_InvestmentIncomeInterest	$ 1,528,975us-gaap_InvestmentIncomeInterest

Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7(b))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration