Comprehensive Income (Components of Accumulated Other Comprehensive Income) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 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	780	1	1,085	9
OCI before reclassifications, Defined Benefit Pension and Post Retirement Plans	0	0	0	28,600
Amounts reclassified from AOCI, HTM Related	(243)	(307)	(683)	(1,172)
Amounts reclassified from AOCI, All Other	(10,683)	(8,785)	(18,637)	(16,107)
Other comprehensive income (loss)	(18,887)	(2,195)	24,274	(36,957)
Other Comprehensive Income, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax	247	513	742	30,839
Ending Balance, September 30, 2014	49,125		49,125
Available-for-sale Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2013			51,635
OCI before reclassifications			41,767
Other comprehensive income (loss)			23,130
Ending Balance, September 30, 2014	74,765		74,765
Investments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2013			51,503
OCI before reclassifications			41,767
Amounts reclassified from AOCI			(18,235)
Other comprehensive income (loss)			23,532
Ending Balance, September 30, 2014	75,035		75,035
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)			1,085
Ending Balance, September 30, 2014	(514)		(514)
Accumulated Net Unrealized Investment Gain (Loss) [Member] | Held-to-maturity Securities [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2013			1,467
OCI before reclassifications			0
Other comprehensive income (loss)			(683)
Ending Balance, September 30, 2014	784		784
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			742
Ending Balance, September 30, 2014	(25,910)		(25,910)
Accumulated other comprehensive income [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance,December 31, 2013			24,851
OCI before reclassifications			41,767
Amounts reclassified from AOCI			(17,493)
Other comprehensive income (loss)			24,274	(36,957)
Ending Balance, September 30, 2014	$ 49,125		$ 49,125