Consolidated Statements Of Comprehensive Income (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net change in unrealized gains on securities, taxes	$ (135,743)	$ 231,472	$ (141,037)
Net change in other-than-temporary impairment gains recognized in other comprehensive income, taxes	(90)	(1,382)	(4,563)
Net change in foreign currency translation, taxes	2,745	8,162	(3,500)
Amortization of pension and postretirement unrecognized net periodic benefit cost, taxes	$ 26,534	$ (51,302)	$ (163)

Amount of tax expense (benefit), before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

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

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Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Amount of tax (expense) benefit, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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

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Amount of tax (expense) benefit of other than temporary impairment (OTTI) on investment in available-for-sale debt security, recognized in other comprehensive loss, attributable to the parent entity.

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