Supplemental Comprehensive Income Disclosures (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning Balance	$ 1,259	$ 2,001
Other comprehensive (loss) income before reclassification adjustment	(2,780)	65
Amounts reclassified from accumulated other comprehensive income (loss)	1,209	974
Other comprehensive income (loss)	(1,571)	1,039
Accumulated Other Comprehensive Income (Loss), Ending Balance	(312)	3,040
Unrealized holding gains on securities arising during the period	(2,780)	65
Accumulated Defined Benefit Plans Adjustment [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Beginning Balance	138	332
Other comprehensive (loss) income before reclassification adjustment	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
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
Amounts reclassified from accumulated other comprehensive income (loss)	1,209	974
Other comprehensive income (loss)	(1,571)	1,039
Accumulated Other Comprehensive Income (Loss), Ending Balance	$ (450)	$ 2,708