XML 63 R65.htm IDEA: XBRL DOCUMENT
v2.3.0.15

Discontinued Operations (Narrative) (Details) (USD $) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2011 years securities | Sep. 30, 2010 | Sep. 30, 2011 years securities | Sep. 30, 2010 | Dec. 31, 2009
Discontinued Operations [Abstract] |  |  |  |  |
Percentage of interest sold in Selective HR |  |  |  |  | 100.00%
Period over which proceeds are scheduled to be received | 10 |  | 10 |  |
Estimated sales price of Selective HR | $ 5,900,000 |  | $ 5,900,000 |  |
Sales price received on subsidiary | 2,500,000 |  | 2,500,000 |  |
After-tax charge | $ (650,000) | $ (1,634,000) | $ (650,000) | $ (3,749,000) |

X
- Definition This item represents the estimated proceeds associated with the sale of a subsidiary. + Details
Name: | sigi_EstimatedSalesPriceOfSubsidiary
Namespace Prefix: | sigi
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition This item represents the percentage of the company's interest in its subsidiary that was sold. + Details
Name: | sigi_PercentageOfInterestSoldInSubsidiary
Namespace Prefix: | sigi
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The number of years over which the proceeds from sale of subsidiary are scheduled to be received. + Details
Name: | sigi_PeriodOverWhichProceedsAreScheduledToBeReceived
Namespace Prefix: | sigi
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of sales price for sale of subsidiary that has been received as of the balance sheet date. + Details
Name: | sigi_SalesPriceReceivedOnSubsidiary
Namespace Prefix: | sigi
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Gain (loss) after tax expense or benefit, not previously recognized and resulting from the sale of a business component, which is recognized at the date of sale. A gain (loss) reflects the amount by which the consideration received exceeds (is exceeded by) the net carrying amount (reflecting previous provisions for loss on disposal, if any) of the disposal group. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e957-107759 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 43 -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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 144 -Paragraph 47 -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. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 + Details
Name: | us-gaap_DiscontinuedOperationGainLossOnDisposalOfDiscontinuedOperationNetOfTax
Namespace Prefix: | us-gaap
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Details
Name: | us-gaap_DiscontinuedOperationsAndDisposalGroupsAbstract
Namespace Prefix: | us-gaap
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration