XML 52 R77.htm IDEA: XBRL DOCUMENT v2.4.1.9

Fair Value Measurements (Changes in Fair Value of Securities Using Level 3 Inputs) (Details) (USD $)
In Thousands, unless otherwise specified

12 Months Ended

Dec. 31, 2013

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]

Fair Value, Beginning Balance

$ 42,277us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue

Total net (losses) gains for the period included in OCI

4,089us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss

^[1]

Total net (losses) gains for the period included in net income

(1,195)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1

^[2],[3]

Purchases

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases

Sales

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales

Issuances

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues

Settlements

(4,660)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements

Transfers into Level 3

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3

Transfers out of Level 3

(37,611)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3

Fair Value, Ending Balance

2,900us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue

Equity Securities [Member]

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]

Fair Value, Beginning Balance

3,607us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= us-gaap_EquitySecuritiesMember

Total net (losses) gains for the period included in OCI

3,935us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_InvestmentTypeAxis
= us-gaap_EquitySecuritiesMember

^[1]

Total net (losses) gains for the period included in net income

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_InvestmentTypeAxis
= us-gaap_EquitySecuritiesMember

^[2],[3]

Purchases

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_InvestmentTypeAxis
= us-gaap_EquitySecuritiesMember

Sales

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
/ us-gaap_InvestmentTypeAxis
= us-gaap_EquitySecuritiesMember

Issuances

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
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= us-gaap_EquitySecuritiesMember

Settlements

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_InvestmentTypeAxis
= us-gaap_EquitySecuritiesMember

Transfers into Level 3

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
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= us-gaap_EquitySecuritiesMember

Transfers out of Level 3

(4,642)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_EquitySecuritiesMember

Fair Value, Ending Balance

2,900us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= us-gaap_EquitySecuritiesMember

AFS Fixed Income Securities [Member] | U.S. Government and Government Agencies [Member]

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]

Fair Value, Beginning Balance

19,789us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_USTreasuryAndGovernmentMember

Total net (losses) gains for the period included in OCI

(537)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_USTreasuryAndGovernmentMember

^[1]

Total net (losses) gains for the period included in net income

(76)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_USTreasuryAndGovernmentMember

^[2],[3]

Purchases

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_FairValueByAssetClassAxis
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= us-gaap_USTreasuryAndGovernmentMember

Sales

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
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/ us-gaap_InvestmentTypeAxis
= us-gaap_USTreasuryAndGovernmentMember

Issuances

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
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= us-gaap_USTreasuryAndGovernmentMember

Settlements

(1,847)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
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Transfers into Level 3

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Transfers out of Level 3

(17,329)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
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/ us-gaap_InvestmentTypeAxis
= us-gaap_USTreasuryAndGovernmentMember

Fair Value, Ending Balance

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
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/ us-gaap_InvestmentTypeAxis
= us-gaap_USTreasuryAndGovernmentMember

AFS Fixed Income Securities [Member] | Corporate Securities [Member]

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]

Fair Value, Beginning Balance

2,946us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_FairValueByAssetClassAxis
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/ us-gaap_InvestmentTypeAxis
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Total net (losses) gains for the period included in OCI

(7)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember

^[1]

Total net (losses) gains for the period included in net income

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember

^[2],[3]

Purchases

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
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Sales

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
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Issuances

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
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/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember

Settlements

(168)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_FairValueByAssetClassAxis
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/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember

Transfers into Level 3

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
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/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember

Transfers out of Level 3

(2,771)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember

Fair Value, Ending Balance

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember

AFS Fixed Income Securities [Member] | Asset-backed Securities [Member]

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]

Fair Value, Beginning Balance

6,068us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember

Total net (losses) gains for the period included in OCI

(74)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember

^[1]

Total net (losses) gains for the period included in net income

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember

^[2],[3]

Purchases

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember

Sales

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember

Issuances

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
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= us-gaap_AssetBackedSecuritiesMember

Settlements

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_FairValueByAssetClassAxis
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/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember

Transfers into Level 3

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
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= us-gaap_AssetBackedSecuritiesMember

Transfers out of Level 3

(5,994)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember

Fair Value, Ending Balance

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember

AFS Fixed Income Securities [Member] | Commercial Mortgage-backed Securities (CMBS) [Member]

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]

Fair Value, Beginning Balance

7,162us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
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Total net (losses) gains for the period included in OCI

772us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_CommercialMortgageBackedSecuritiesMember

^[1]

Total net (losses) gains for the period included in net income

361us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
= us-gaap_CommercialMortgageBackedSecuritiesMember

^[2],[3]

Purchases

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_FairValueByAssetClassAxis
= sigi_AfsFixedMaturitySecuritiesMember
/ us-gaap_InvestmentTypeAxis
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Sales

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
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Issuances

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
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Settlements

(2,420)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
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Transfers into Level 3

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
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Transfers out of Level 3

(5,875)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
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/ us-gaap_InvestmentTypeAxis
= us-gaap_CommercialMortgageBackedSecuritiesMember

Fair Value, Ending Balance

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_FairValueByAssetClassAxis
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Receivable For Proceeds From Divestiture Of Businesses [Member]

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]

Fair Value, Beginning Balance

2,705us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_FairValueByAssetClassAxis
= sigi_ReceivableForProceedsFromDivestitureOfBusinessesMember

Total net (losses) gains for the period included in OCI

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_FairValueByAssetClassAxis
= sigi_ReceivableForProceedsFromDivestitureOfBusinessesMember

^[1]

Total net (losses) gains for the period included in net income

(1,480)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_FairValueByAssetClassAxis
= sigi_ReceivableForProceedsFromDivestitureOfBusinessesMember

^[2],[3]

Purchases

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_FairValueByAssetClassAxis
= sigi_ReceivableForProceedsFromDivestitureOfBusinessesMember

Sales

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
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Issuances

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
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Settlements

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Transfers into Level 3

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
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Transfers out of Level 3

(1,000)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
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Fair Value, Ending Balance

0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_FairValueByAssetClassAxis
= sigi_ReceivableForProceedsFromDivestitureOfBusinessesMember

Fair Value, Inputs, Level 3 [Member] | AFS Fixed Income Securities [Member]

Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]

Transfers out of Level 3

$ (32,000)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
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[1]	Amounts are reported in “Unrealized holding gains (losses) arising during period” on the Consolidated Statements of Comprehensive Income.
[2]	For the receivable related to the sale of Selective HR, amounts in “Loss on disposal of discontinued operations, net of tax” relate to an impairment charge and amounts in “Other income” relate to interest accretion on the Consolidated Statements of Income.
[3]	Amounts are reported in “Net realized gains” for realized gains and losses and “Net investment income earned” for amortization of securities on the Consolidated Statements of Income.

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

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-Subparagraph (c)(1)

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Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1a)

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Amount of issuances of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

+ References

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-Publisher FASB

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