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v2.4.1.9

Investments (Fair Value and Gross Pre-Tax Net Unrealized Unrecognized Loss of Securities By Length of Time) (Details) (USD $) In Thousands, unless otherwise specified | Dec. 31, 2014 | Dec. 31, 2013
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AFS Fair Value, Less than 12 months | $ 466,387 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue |  | $ 1,411,803 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue |
AFS Unrealized Losses, Less than 12 months | (2,408)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss | [1] | (49,106)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss | [1]
AFS Fair Value, 12 months or longer | 442,058 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue |  | 40,731 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue |
AFS Unrealized Loss, 12 Months or Longer | (8,170)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss | [1] | (2,865)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss | [1]
HTM Fair Value, Less than 12 months | 196 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue |  | 65 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue |
HTM Unrealized Losses, Less than 12 months | (3)us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss | [1] | (5)us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss | [1]
HTM Unrecognized Gains, Less than 12 months | 1 sigi_HeldToMaturitySecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionLessThanTwelveMonths |  | 5 sigi_HeldToMaturitySecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionLessThanTwelveMonths |
HTM Fair Value, 12 months or longer | 2,235 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue |  | 2,931 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue |
HTM Unrealized Losses, 12 Months or Longer | (455)us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss | [1] | (675)us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss | [1]
HTM Unrecognized Gains, 12 months or longer | 439 sigi_HeldToMaturitySecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionTwelveMonthsorLonger |  | 635 sigi_HeldToMaturitySecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionTwelveMonthsorLonger |
Available For Sale and Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value | 466,583 sigi_AvailableForSaleandHeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue |  | 1,411,868 sigi_AvailableForSaleandHeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue |
Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Aggregate Losses | 2,411 sigi_AvailableForSaleAndHeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsAggregateLosses | [1] | 49,111 sigi_AvailableForSaleAndHeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsAggregateLosses | [1]
Held To Maturity And Available For Sale Securities Unrecognized Gains Losses Aggregate Continuous Unrealized Loss Position Less Than Twelve Months | 1 sigi_HeldToMaturityAndAvailableForSaleSecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionLessThanTwelveMonths |  | 5 sigi_HeldToMaturityAndAvailableForSaleSecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionLessThanTwelveMonths |
Available For Sale and Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value | 444,293 sigi_AvailableForSaleandHeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue |  | 43,662 sigi_AvailableForSaleandHeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue |
Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Aggregate Losses | 8,625 sigi_AvailableForSaleAndHeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerAggregateLosses | [1] | 3,540 sigi_AvailableForSaleAndHeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerAggregateLosses | [1]
Held To Maturity And Available For Sale Securities Unrecognized Gains Losses Aggregate Continuous Unrealized Loss Position For Twelve Months Or Longer | 439 sigi_HeldToMaturityAndAvailableForSaleSecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionForTwelveMonthsOrLonger |  | 635 sigi_HeldToMaturityAndAvailableForSaleSecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionForTwelveMonthsOrLonger |
Obligations of States and Political Subdivisions [Member] |  |  |  |
HTM Fair Value, Less than 12 months | 196 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember |  | 65 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember |
HTM Unrealized Losses, Less than 12 months | (3)us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember | [1] | (5)us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember | [1]
HTM Unrecognized Gains, Less than 12 months | 1 sigi_HeldToMaturitySecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionLessThanTwelveMonths / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember |  | 5 sigi_HeldToMaturitySecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionLessThanTwelveMonths / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember |
HTM Fair Value, 12 months or longer | 0 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember |  | 441 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember |
HTM Unrealized Losses, 12 Months or Longer | 0 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember | [1] | (20)us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember | [1]
HTM Unrecognized Gains, 12 months or longer | 0 sigi_HeldToMaturitySecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionTwelveMonthsorLonger / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember |  | 14 sigi_HeldToMaturitySecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionTwelveMonthsorLonger / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember |
Asset-backed Securities [Member] |  |  |  |
HTM Fair Value, Less than 12 months | 0 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember |  | 0 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember |
HTM Unrealized Losses, Less than 12 months | 0 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember | [1] | 0 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember | [1]
HTM Unrecognized Gains, Less than 12 months | 0 sigi_HeldToMaturitySecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionLessThanTwelveMonths / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember |  | 0 sigi_HeldToMaturitySecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionLessThanTwelveMonths / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember |
HTM Fair Value, 12 months or longer | 2,235 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember |  | 2,490 us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember |
HTM Unrealized Losses, 12 Months or Longer | (455)us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember | [1] | (655)us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember | [1]
HTM Unrecognized Gains, 12 months or longer | 439 sigi_HeldToMaturitySecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionTwelveMonthsorLonger / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember |  | 621 sigi_HeldToMaturitySecuritiesUnrecognizedGainsLossesAggregateContinuousUnrealizedLossPositionTwelveMonthsorLonger / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember |
AFS Fixed Income Securities [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 461,125 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |  | 1,410,679 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Losses, Less than 12 months | (2,072)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1] | (49,010)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fair Value, 12 months or longer | 442,058 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |  | 40,731 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Loss, 12 Months or Longer | (8,170)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1] | (2,865)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fixed Income Securities [Member] | U.S. Government and Government Agencies [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 7,567 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |  | 16,955 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Losses, Less than 12 months | (13)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1] | (500)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fair Value, 12 months or longer | 10,866 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |  | 507 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Loss, 12 Months or Longer | (115)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1] | (4)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fixed Income Securities [Member] | Foreign Government [Member] |  |  |  |
AFS Fair Value, Less than 12 months |  |  | 2,029 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Losses, Less than 12 months |  |  | (30)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fair Value, 12 months or longer |  |  | 2,955 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Loss, 12 Months or Longer |  |  | (42)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fixed Income Securities [Member] | Obligations of States and Political Subdivisions [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 47,510 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |  | 442,531 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Losses, Less than 12 months | (105)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1] | (19,120)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fair Value, 12 months or longer | 64,018 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |  | 13,530 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Loss, 12 Months or Longer | (624)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1] | (905)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fixed Income Securities [Member] | Corporate Securities [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 276,648 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |  | 511,100 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Losses, Less than 12 months | (1,734)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1] | (15,911)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fair Value, 12 months or longer | 153,613 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |  | 14,771 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Loss, 12 Months or Longer | (4,075)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1] | (1,138)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_CorporateDebtSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fixed Income Securities [Member] | Asset-backed Securities [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 113,202 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |  | 68,725 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Losses, Less than 12 months | (178)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1] | (468)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fair Value, 12 months or longer | 15,618 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |  | 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Loss, 12 Months or Longer | (195)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1] | 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_AssetBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fixed Income Securities [Member] | Commercial Mortgage Backed Securities [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 12,799 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_CommercialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |  | 100,396 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_CommercialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Losses, Less than 12 months | (34)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_CommercialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1] | (2,950)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_CommercialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fair Value, 12 months or longer | 59,219 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_CommercialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |  | 6,298 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_CommercialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Loss, 12 Months or Longer | (743)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_CommercialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1] | (516)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_CommercialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fixed Income Securities [Member] | Residential Mortgage Backed Securities [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 3,399 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |  | 268,943 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / us-gaap_InvestmentTypeAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Losses, Less than 12 months | (8)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1] | (10,031)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
AFS Fair Value, 12 months or longer | 138,724 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |  | 2,670 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / us-gaap_InvestmentTypeAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember |
AFS Unrealized Loss, 12 Months or Longer | (2,418)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1] | (260)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / us-gaap_InvestmentTypeAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = sigi_AfsFixedMaturitySecuritiesMember | [1]
Equity Securities [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 5,262 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = us-gaap_EquitySecuritiesMember |  | 1,124 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = us-gaap_EquitySecuritiesMember |
AFS Unrealized Losses, Less than 12 months | (336)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = us-gaap_EquitySecuritiesMember | [1] | (96)us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = us-gaap_EquitySecuritiesMember | [1]
AFS Fair Value, 12 months or longer | 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = us-gaap_EquitySecuritiesMember |  | 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = us-gaap_EquitySecuritiesMember |
AFS Unrealized Loss, 12 Months or Longer | $ 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = us-gaap_EquitySecuritiesMember | [1] | $ 0 us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss / sigi_ScheduleOfFairValueAndGrossPreTaxUnrealizedUnrecognizedLossOfSecuritiesByLengthOfTimeAxis = us-gaap_EquitySecuritiesMember | [1]
[1] | Gross unrealized losses include non-OTTI unrealized amounts and OTTI losses recognized in AOCI. In addition, this column includes remaining unrealized gain or loss amounts on securities that were transferred to an HTM designation in the first quarter of 2009 for those securities that are in a net unrealized/unrecognized loss position.

X
- Definition This item represents the unrealized holding gains/losses of an available-for sale ("AFS") and held-to-maturity("HTM") security that has been in a continuous unrealized/unrecognized loss position for less than twelve months. The AFS unrealized holding losses represent the excess of amortized cost over fair value of securities. The HTM unrealized holding gains/losses represent the remaining unrealized gain/loss amounts on securities that were transferred to a HTM designation from an AFS designation as well as other-than-temporary impairment losses that are recognized in accumulated other comprehensive income. + References No definition available. + Details
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- Definition This item represents the fair value of securities categorized as available-for-sale and held-to-maturity that have been in a continuous unrealized loss position for less than twelve months. + References No definition available. + Details
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- Definition This item represents the unrealized holding gains/losses of an available-for sale ("AFS") and held-to-maturity("HTM") security that has been in a continuous unrealized/unrecognized loss position for twelve months or longer. The AFS unrealized holding losses represent the excess of amortized cost over fair value of securities. The HTM unrealized holding gains/losses represent the remaining unrealized gain/loss amounts on securities that were transferred to a HTM designation from an AFS designation as well as other-than-temporary impairment losses that are recognized in accumulated other comprehensive income. + References No definition available. + Details
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- Definition This item represents the fair value of securities categorized as available-for-sale and held-to-maturity that have been in a continuous unrealized loss position for twelve months or longer. + References No definition available. + Details
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- Definition This item represents the unrecognized holding gains/losses of a security that has been in a continuous unrealized/unrecognized loss position for twelve months or longer. The unrecognized holding gains/losses represent the market value fluctuations from the later of: (i) the date a security is designated as held-to-maturity; or (ii) the date that an other-than-temporary- impairment charge is recognized on a held-to-maturity security. + References No definition available. + Details
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- Definition This item represents the unrecognized holding gains/losses of a security that has been in a continuous unrealized/unrecognized loss position for less than twelve months. The unrecognized holding gains/losses represent the market value fluctuations from the later of: (i) the date a security is designated as held-to-maturity; or (ii) the date that an other-than-temporary- impairment charge is recognized on a held-to-maturity security. + References No definition available. + Details
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- Definition This item represents the unrecognized holding gains/losses of a held-to-maturity security that has been in a continuous unrealized/unrecognized loss position for less than twelve months. The unrecognized holding gains/losses represent the market value fluctuations from the later of: (i) the date a security is designated as held-to-maturity; or (ii) the date that an other-than-temporary- impairment charge is recognized on a held-to-maturity security. + References No definition available. + Details
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- Definition This item represents the unrecognized holding gains/losses of a held-to-maturity security that has been in a continuous unrealized/unrecognized loss position for twelve months or longer. The unrecognized holding gains/losses represent the market value fluctuations from the later of: (i) the date a security is designated as held-to-maturity; or (ii) the date that an other-than-temporary- impairment charge is recognized on a held-to-maturity security. + References No definition available. + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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