Income Taxes (Net Deferred Income Tax Assets) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Income Taxes [Abstract]
Loss reserve	$ 153,978	$ 146,781
Foreign tax credits	64,902	74,255
Alternative minimum tax credits	44,954	93,336
Unearned premium reserve	44,582	45,368
Net unrecognized losses on benefit plans	40,377	20,944
Deferred gain on reinsurance	35,231	29,965
Investment impairments	13,841	2,344
Benefit plan liabilities	9,873	7,968
Uncollectible reinsurance reserve	5,237	5,534
Deferred expenses	3,076	2,695
Other assets	17,357us-gaap_DeferredTaxAssetsOther	12,579us-gaap_DeferredTaxAssetsOther
Deferred Tax Assets, Net, Total	433,408us-gaap_DeferredTaxAssetsNet	441,769us-gaap_DeferredTaxAssetsNet
Net fair value income	403,731	350,747
Deferred acquisition costs	38,636	39,344
Net unrealized investment gains	25,516	38,750
Net unrealized foreign currency gains		27,735
Gain on tender of debt	21,916	27,395
Bond market discount	3,043	1,629
Other liabilities	13,158us-gaap_DeferredTaxLiabilitiesOther	7,458us-gaap_DeferredTaxLiabilitiesOther
Total deferred tax liabilities	506,000us-gaap_DeferredTaxLiabilities	493,058us-gaap_DeferredTaxLiabilities
Net deferred tax assets/(liabilities)	$ (72,592)us-gaap_DeferredTaxAssetsLiabilitiesNet	$ (51,289)us-gaap_DeferredTaxAssetsLiabilitiesNet

Deferred Tax Asset Investment Impairments

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Deferred Tax Assets, Net Unrecognized Losses On Benefit Plans

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

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Amount of deferred tax liability attributable to taxable temporary differences from unrealized gains on foreign currency transactions.

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Amount of deferred tax liability attributable to taxable temporary differences from unrealized gains on trading securities.

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