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Such gross unrealized losses are included in other comprehensive income in the statement of shareholders' equity, unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. Recognized in earnings is all or a portion of the unrealized holding loss, during the period of the hedge, of an Available-for-sale Security that is designated as being hedged in a fair value hedge, other than temporary declines in fair value below cost basis of equity securities, and debt securities which an other than temporary decline in fair value is due to credit losses or which the entity intends to sell or it is more likely than not that the entity will be required to sell the security before recovery of its amortized cost basis. 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Such securities are reported at fair value, with unrealized gains and losses excluded from earnings and reported in a separate component of shareholders' equity (other comprehensive income), unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis. 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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 7 -Footnote 2 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 19 false 24 Unrealized gains 2 ceg_AvailableForSaleSecuritiesGrossUnrealizedGain ceg false credit instant The gross unrealized gains for securities which are categorized neither as held-to-maturity nor trading securities. false false false false false false false false false false false terselabel false 1 false false false false 0 0 false false false 2 false true false false 2800000 2.8 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:monetaryItemType monetary The gross unrealized gains for securities which are categorized neither as held-to-maturity nor trading securities. 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All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis. 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Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 7 -Footnote 2 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 19 false 34 Unrealized gains 2 ceg_AvailableForSaleSecuritiesGrossUnrealizedGain ceg false credit instant The gross unrealized gains for securities which are categorized neither as held-to-maturity nor trading securities. false false false false false false false false false false false terselabel false 1 false true false false 41500000 41.5 false false false 2 false false false false 0 0 false false false 3 false false false false 0 0 false false false 4 false false false false 0 0 false false false xbrli:monetaryItemType monetary The gross unrealized gains for securities which are categorized neither as held-to-maturity nor trading securities. 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Such gross unrealized losses are included in other comprehensive income in the statement of shareholders' equity, unless the Available-for-sale Security is designated as a hedge or is determined to have had an other than temporary decline in fair value below its amortized cost basis. Recognized in earnings is all or a portion of the unrealized holding loss, during the period of the hedge, of an Available-for-sale Security that is designated as being hedged in a fair value hedge, other than temporary declines in fair value below cost basis of equity securities, and debt securities which an other than temporary decline in fair value is due to credit losses or which the entity intends to sell or it is more likely than not that the entity will be required to sell the security before recovery of its amortized cost basis. 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All or a portion of the unrealized holding gain or loss of an Available-for-sale Security that is designated as being hedged in a fair value hedge shall be recognized in earnings during the period of the hedge, as should other than temporary declines in fair value below costs basis. 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