Supplemental Comprehensive Income Disclosures (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning Balance			$ 1,259	$ 2,001
Unrealized holding gains on securities arising during the period	(18,254)	654	(21,034)	719
Amounts reclassified from accumulated other comprehensive income (loss)			3,053	114
Other comprehensive income (loss)	(16,410)	(206)	(17,981)	833
Accumulated Other Comprehensive Income (Loss), Ending Balance	(16,722)	2,834	(16,722)	2,834
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning Balance			138	332
Unrealized holding gains on securities arising during the period			0	0
Amounts reclassified from accumulated other comprehensive income (loss)			0	0
Other comprehensive income (loss)			0	0
Accumulated Other Comprehensive Income (Loss), Ending Balance	138	332	138	332
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning Balance			1,121	1,669
Unrealized holding gains on securities arising during the period			(21,034)	719
Amounts reclassified from accumulated other comprehensive income (loss)			3,053	114
Other comprehensive income (loss)			(17,981)	833
Accumulated Other Comprehensive Income (Loss), Ending Balance	$ (16,860)	$ 2,502	$ (16,860)	$ 2,502