XML 49 R65.htm IDEA: XBRL DOCUMENT
v2.4.0.6

Commitments and Contingencies (Narrative) (Details) (Other Investments [Member], USD $) In Thousands, unless otherwise specified | Sep. 30, 2012
--- | ---
Other Investments [Member] |
Remaining Commitment | $ 64,846

X
- Definition This item represents contractual obligations to invest additional amounts on our other investment portfolio. These additional investments may or may not be required. + References No definition available. + Details
Name: | sigi_RemainingCommitment
Namespace Prefix: | sigi_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant