Consolidated Statement Of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income	$ 470,907us-gaap_NetIncomeLoss	$ 488,907us-gaap_NetIncomeLoss	$ 483,705us-gaap_NetIncomeLoss
Other comprehensive income (loss):
Change in unrealized gains on securities, net of taxes of $(135,743), $231,472, and $(141,037), respectively	267,011	(455,808)	268,106
Change in other-than-temporary impairment gains, net of taxes of $(90), $(1,382), and $(4,563), respectively	167	2,566	8,474
Change in foreign currency translation, net of taxes of $2,745, $8,162, and $(3,500), respectively	(88,944)	(45,649)	(4,036)
Amortization of pension and postretirement unrecognized net periodic benefit cost and change in funded status, net of taxes of $26,534, $(51,302), and $(163), respectively	(49,297)	95,318	283
Total other comprehensive income (loss)	128,937	(403,573)	272,827
Total comprehensive income	$ 599,844us-gaap_ComprehensiveIncomeNetOfTax	$ 85,334us-gaap_ComprehensiveIncomeNetOfTax	$ 756,532us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and 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 after tax and 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.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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

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

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