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Gross loss realized on the sale of equity securities not classified as available-for-sale, trading, or held-to-maturity.

No definition available.

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This item represents the gross loss realized on the disposal of held-to-maturity securities during the period.

No definition available.

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This item represents the gross gain realized on the disposal of held-to-maturity securities during the period.

No definition available.

Name:	sigi_HeldToMaturitySecuritiesRealizedGain
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This item represents the gross profit realized on the sale of other investments.

No definition available.

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This item represents the gross loss realized on the sale of other investments.

No definition available.

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The cash inflow associated with the sale of equity securities not classified as trading or available-for-sale.

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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Gross realized gains on short term investments.

No definition available.

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This item represents the gross loss realized on the sale of short-term investments.

No definition available.

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Aggregate net change in unrealized gains or losses on the equity portfolio recognized in net income for the period.

No definition available.

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The net gain (loss) realized from the sale, exchange, redemption, or retirement of securities, not separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

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-Publisher FASB
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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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This item represents the total realized gain (loss) included in earnings for the period as a result of selling marketable securities categorized as trading, available-for-sale, or held-to-maturity.

No definition available.

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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The cash inflow associated with the sale of equity securities classified as available-for-sale securities.

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The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period.

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