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Investment Securities (Details 4) (Available for sale investments, USD $) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2013 | Jun. 30, 2012 | Jun. 30, 2013 | Jun. 30, 2012
Available for sale investments |  |  |  |
Credit-related impairment charges on investments recognized in earnings |  |  |  |
Impairment charges, after tax, recognized during period | $ 217,050 | $ 144,300 | $ 472,550 | $ 265,200
Reconciliation of credit-related impairment charges on investments recognized in earnings |  |  |  |
Balance at the beginning | 10,742,000 | 9,579,000 | 10,432,000 | 9,393,000
Impairment charges recognized during period | 417,000 | 222,000 | 727,000 | 408,000
Balance at the end | $ 11,159,000 | $ 9,801,000 | $ 11,159,000 | $ 9,801,000

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- Definition This item represents an increase to the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security held for which a previous OTTI was recognized and the investor does not intend to sell the debt security and it is not more likely than not that the investor will be required to sell the debt security before recovery of its amortized cost basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27340-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 18B -Subparagraph e -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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