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Comprehensive Income (Components of Accumulated Other Comprehensive Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2013			$ 24,851
Amounts reclassified into Net Income: Non-credit other-than-temporary impairments	305	3	305	8
OCI before reclassifications, Defined Benefit Pension and Post Retirement Plans	0	0	0	28,600
Amounts reclassified from AOCI, HTM Related	(144)	(399)	(440)	(865)
Amounts reclassified from AOCI, All Other	(3,255)	(3,438)	(7,954)	(7,322)
Other comprehensive income (loss)	26,483	(62,643)	43,161	(34,762)
Other Comprehensive Income, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	248	513	495	30,326
Ending Balance, June 30, 2014	68,012		68,012
Available-for-sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2013			51,635
OCI before reclassifications			50,755
Other comprehensive income (loss)			42,801
Ending Balance, June 30, 2014	94,436		94,436
Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2013			51,503
OCI before reclassifications			50,755
Amounts reclassified from AOCI			(8,089)
Other comprehensive income (loss)			42,666
Ending Balance, June 30, 2014	94,169		94,169
Accumulated Other-than-Temporary Impairment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2013			(1,599)
OCI before reclassifications			0
Other comprehensive income (loss)			305
Ending Balance, June 30, 2014	(1,294)		(1,294)
Accumulated Net Unrealized Investment Gain (Loss) [Member] | Held To Maturity Fixed Income Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2013			1,467
OCI before reclassifications			0
Other comprehensive income (loss)			(440)
Ending Balance, June 30, 2014	1,027		1,027
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2013			(26,652)
Other Comprehensive Income, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax			495
Ending Balance, June 30, 2014	(26,157)		(26,157)
Accumulated other comprehensive income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2013			24,851
OCI before reclassifications			50,755
Amounts reclassified from AOCI			(7,594)
Other comprehensive income (loss)			43,161	(34,762)
Ending Balance, June 30, 2014	$ 68,012		$ 68,012

X

- Definition

Net of tax amount of the reclassification adjustment related 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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Amount after tax of reclassification adjustment from accumulated other comprehensive income related to non-credit OTTI 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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