XML 74 R38.htm IDEA: XBRL DOCUMENT v2.4.0.8

Investments (Investments Pledged as Collateral) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014
Schedule of Available-for-sale Securities [Line Items]
Fixed Income Securities PledgedFor FHLBI Collateral	$ 61.6
Securities Pledged As Collateral For Reinsurance Obligations	16.4
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	26.0
Securities Pledged As Collateral	104.0
Outstanding Borrowing With The Federal Home Loan Bank Of Indianapolis	58
U.S. Government and Government Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed Income Securities PledgedFor FHLBI Collateral	22.9
Securities Pledged As Collateral For Reinsurance Obligations	0
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	26.0
Securities Pledged As Collateral	48.9
Obligations of States and Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed Income Securities PledgedFor FHLBI Collateral	0
Securities Pledged As Collateral For Reinsurance Obligations	5.7
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	0
Securities Pledged As Collateral	5.7
Corporate Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed Income Securities PledgedFor FHLBI Collateral	0
Securities Pledged As Collateral For Reinsurance Obligations	5.3
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	0
Securities Pledged As Collateral	5.3
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed Income Securities PledgedFor FHLBI Collateral	0
Securities Pledged As Collateral For Reinsurance Obligations	2.0
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	0
Securities Pledged As Collateral	2.0
Commercial Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed Income Securities PledgedFor FHLBI Collateral	1.9
Securities Pledged As Collateral For Reinsurance Obligations	0
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	0
Securities Pledged As Collateral	1.9
Residential Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed Income Securities PledgedFor FHLBI Collateral	36.8
Securities Pledged As Collateral For Reinsurance Obligations	3.2
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	0
Securities Pledged As Collateral	40.0
Fixed Income Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed Income Securities PledgedFor FHLBI Collateral	61.6
Securities Pledged As Collateral For Reinsurance Obligations	16.2
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	26.0
Securities Pledged As Collateral	103.8
Short-Term Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Fixed Income Securities PledgedFor FHLBI Collateral	0
Securities Pledged As Collateral For Reinsurance Obligations	0.2
Carrying Value Bonds On Deposit With Various State And Regulatory Agencies	0
Securities Pledged As Collateral	$ 0.2

X

- Definition

This item represents the carrying value of debt securities, both held-to-maturity securities and available-for-sale securities, that are on deposit with various state and regulatory agencies to comply with insurance laws.

+ References

No definition available.

+ Details

Name:	sigi_CarryingValueBondsOnDepositWithVariousStateandRegulatoryAgencies
Namespace Prefix:	sigi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Total value amount of investments pledged as collateral

+ References

No definition available.

+ Details

Name:	sigi_SecuritiesPledgedAsCollateral
Namespace Prefix:	sigi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

The carrying value of investments pledged as collateral for reinsurance obligations

+ References

No definition available.

+ Details

Name:	sigi_SecuritiesPledgedAsCollateralForReinsuranceObligations
Namespace Prefix:	sigi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

+ Details

Name:	us-gaap_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresCollateralPledged1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.16)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 16

-Article 9



Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64702-112823

+ Details

Name:	us-gaap_FederalHomeLoanBankAdvancesLongTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Details

Name:	us-gaap_ScheduleOfAvailableForSaleSecuritiesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration