2.4.0.82409402 - Disclosure - Investments (Investment Gains and Losses) (Details)truefalseIn Thousands, unless otherwise specifiedfalse1false USDfalsefalse$D2013Q2http://www.sec.gov/CIK0000070684duration2013-04-01T00:00:002013-06-30T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$D2012Q2http://www.sec.gov/CIK0000070684duration2012-04-01T00:00:002012-06-30T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$3false USDfalsefalse$D2013Q2YTDhttp://www.sec.gov/CIK0000070684duration2013-01-01T00:00:002013-06-30T00:00:00numberStandardhttp://www.xbrl.org/2003/instancepurexbrli0usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4false USDfalsefalse$D2012Q2YTDhttp://www.sec.gov/CIK0000070684duration2012-01-01T00:00:002012-06-30T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$5false USDfalsefalse$D2012Q4YTDhttp://www.sec.gov/CIK0000070684duration2012-01-01T00:00:002012-12-31T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 4us-gaap_HeldtomaturitySecuritiesOtherDisclosureItemsAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Held to maturity debt securities:2false 4us-gaap_GainsLossesOnSalesOfInvestmentRealEstateus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse00USD$falsetruefalse2truefalsefalse-159000-159USD$falsetruefalse3truefalsefalse00USD$falsetruefalse4truefalsefalse-159000-159USD$falsetruefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 225 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.14(d)) -URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Paragraph 14 -Subparagraph d -Article 9 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher OTS -Name Federal Regulation (FR) -Number Title 12 -Section 563c.102 -Paragraph 13 -Subparagraph g -Chapter V -Subsection II -LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. 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This element is used when other, more specific, elements are not appropriate. This element refers to the gain (loss) included in earnings.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 28 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585 false2Other5false 4us-gaap_GainLossOnInvestmentsExcludingOtherThanTemporaryImpairmentsus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse17790001779USD$falsefalsefalse2truefalsefalse24250002425USD$falsefalsefalse3truefalsefalse41530004153USD$falsefalsefalse4truefalsefalse37910003791USD$falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. true2Net OTTI losses recognized in earnings12true 4us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsRollForwardus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Non-Credit Other-than-Temporary Impairment, Credit Losses Recognized in Other Comprehensive Income (Loss) [Roll Forward]13false 5us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeldus-gaap_truedebitinstantfalsefalsefalsefalsefalsetruefalsefalseperiodStartLabel1truefalsefalse23080002308USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse22470002247USD$falsefalsefalse4truefalsefalse11220001122USD$falsefalsefalse5truefalsefalse11220001122USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27340-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 18B -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Beginning balance, cumulative credit losses related to other-than-temporary impairments14false 5us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSoldus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse00USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse-118000-118USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents reductions in the cumulative amount of credit losses recognized in earnings for an other than temporary impairment (OTTI) of a debt security because of the sale of impaired securities during the period.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27340-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 18B -Subparagraph c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Reductions for securities sold during current period15false 5us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairmentus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse164000164USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse225000225USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse12430001243USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThis 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 no such other than temporary impairment (OTTI) was previously recognized.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -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 b -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. false2Additions for credit losses not previously recognized in other-than-temporary impairments16false 5us-gaap_OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeldus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsetruefalseperiodEndLabel1truefalsefalse24720002472USD$falsefalsefalse2falsefalsefalse00falsefalsefalse3truefalsefalse24720002472USD$falsefalsefalse4falsefalsefalse00falsefalsefalse5truefalsefalse22470002247USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe cumulative amount of credit losses recognized in earnings related to debt securities held for which a portion of an other than temporary impairment (OTTI) was recognized in other comprehensive income (a component of shareholders' equity).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27340-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 18B -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Ending balance, cumulative credit losses related to other-than-temporary impairments17false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalse6false USDtruefalse$D2013Q2_us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_us-gaap_DebtSecuritiesMemberhttp://www.sec.gov/CIK0000070684duration2013-04-01T00:00:002013-06-30T00:00:00falsefalseDebt Securities [Member]us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_DebtSecuritiesMemberus-gaap_MajorTypesOfDebtAndEquitySecuritiesAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Debt Securities [Member]18true 4us-gaap_AvailableForSaleSecuritiesGrossRealizedGainLossNetAbstractus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Available for sale debt securities:19false 5us-gaap_AvailableForSaleSecuritiesGrossRealizedGainsus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse15280001528USD$falsefalsefalse2truefalsefalse25790002579USD$falsefalsefalse3truefalsefalse33240003324USD$falsefalsefalse4truefalsefalse42070004207USD$falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6872113&loc=d3e27357-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 21 -Subparagraph a -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. false2Realized gains on disposal20false 5us-gaap_AvailableForSaleSecuritiesGrossRealizedLossesus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedTerseLabel1truefalsefalse00USD$falsefalsefalse2truefalsefalse00USD$falsefalsefalse3truefalsefalse00USD$falsefalsefalse4truefalsefalse00USD$falsefalsefalse5falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThis item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.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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