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Comprehensive Income (Components of Accumulated Other Comprehensive Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2012			$ 54,040
Amounts reclassified from AOCI, HTM Related	(307)	(219)	(1,172)	(1,236)
Amounts reclassified from AOCI, All Other	(8,785)	674	(16,107)	(2,243)
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	513	928	30,839	2,785
Ending Balance, September 30, 2013	17,083		17,083
Available-for-sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2012			121,391
OCI before reclassifications			(50,473)
Other comprehensive (loss) income			(66,580)
Ending Balance, September 30, 2013	54,811		54,811
Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2012			122,327
OCI before reclassifications			(50,526)
Amounts reclassified from AOCI			(17,270)
Other comprehensive (loss) income			(67,796)
Ending Balance, September 30, 2013	54,531		54,531
Accumulated Other-than-Temporary Impairment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2012			(1,658)
OCI before reclassifications			50
Amounts reclassified from AOCI	1	6	9	177
Other comprehensive (loss) income			59
Ending Balance, September 30, 2013	(1,599)		(1,599)
Accumulated Net Unrealized Investment Gain (Loss) [Member] | Held To Maturity Fixed Maturity Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2012			2,594
OCI before reclassifications			(103)
Other comprehensive (loss) income			(1,275)
Ending Balance, September 30, 2013	1,319		1,319
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2012			(68,287)
OCI before reclassifications, Defined Benefit Pension and Post Retirement Plans	0	0	28,600	0
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax			2,239
Ending Balance, September 30, 2013	(37,448)		(37,448)
Accumulated other comprehensive income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2012			54,040
OCI before reclassifications			(21,926)
Amounts reclassified from AOCI			(15,031)
Other comprehensive (loss) income	(2,195)	26,507	(36,957)	42,717
Ending Balance, September 30, 2013	$ 17,083		$ 17,083

X

- Definition

Net of tax amount of the reclassification adjustment relaated to held-to-maturity securities transferred from the available-for-sale category. This amount includes amortization and amounts realized from the disposal of these securities.

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount after tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

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

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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