2.4.0.82403406 - Disclosure - Investment Securities (Gains and Losses on Securities Available for Sale) (Details)truefalseIn Thousands, unless otherwise specifiedfalse1false USDfalsefalse$D2013Q2http://www.sec.gov/CIK0000320387duration2013-04-01T00:00:002013-06-30T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$D2012Q2http://www.sec.gov/CIK0000320387duration2012-04-01T00:00:002012-06-30T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$3false USDfalsefalse$D2013Q2YTDhttp://www.sec.gov/CIK0000320387duration2013-01-01T00:00:002013-06-30T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4false USDfalsefalse$D2012Q2YTDhttp://www.sec.gov/CIK0000320387duration2012-01-01T00:00:002012-06-30T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 1us-gaap_InvestmentsDebtAndEquitySecuritiesAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Investments, Debt and Equity Securities [Abstract]2false 2us-gaap_AvailableForSaleSecuritiesGrossRealizedGainsLossesSaleProceedsus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse141658000141658USD$falsetruefalse2truefalsefalse88550008855USD$falsetruefalse3truefalsefalse147799000147799USD$falsetruefalse4truefalsefalse4283700042837USD$falsetruefalsexbrli:monetaryItemTypemonetaryThe total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27357-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 21 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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