Accumulated Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Beginning balance, Unrealized gains and Losses on available-for-sale Securities	$ 13,431	$ 12,740
Net Current period other comprehensive other income, Unrealized gains and Losses on available-for-sale Securities	(1,667)	370
Ending balance, Unrealized gains and Losses on available-for-sale Securities	11,764	13,110
Beginning balance,Retirement plans	(20,903)	(23,234)
Net Current period other comprehensive other income, Retirement plans	214	42
Ending balance, Retirement plans	(20,689)	(23,192)
TOTAL Balance	(7,472)	(10,494)
Change in Other comprehensive income before reclassification	(1,665)	368
Amounts reclassified from accumulated other comprehensive income	212	44
Net Current period other comprehensive other income	(1,453)	412
TOTAL Balance	(8,925)	(10,082)
Retirement plans [Member]
Beginning balance,Retirement plans	(20,903)	(23,234)
Change in Other comprehensive income before reclassification, Retirement plans	0	0
Amounts reclassified from accumulated other comprehensive income, Retirement plans	214	42
Net Current period other comprehensive other income, Retirement plans	214	42
Ending balance, Retirement plans	(20,689)	(23,192)
Unrealized gains and Losses on available-for-sale Securities [Member]
Beginning balance, Unrealized gains and Losses on available-for-sale Securities	13,431	12,740
Change in Other comprehensive income before reclassification, Unrealized gains and Losses on available-for-sale Securities	(1,665)	368
Amounts reclassified from accumulated other comprehensive income, Unrealized gains and Losses on available-for-sale Securities	(2)	2
Net Current period other comprehensive other income, Unrealized gains and Losses on available-for-sale Securities	(1,667)	370
Ending balance, Unrealized gains and Losses on available-for-sale Securities	$ 11,764	$ 13,110

Net of tax amount of other comprehensive income after reclassification adjustments.

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Net of tax amount of other comprehensive income before reclassification adjustments.

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Accumulated appreciation or loss, net of tax, in value of the total of available-for-sale securities at the end of an accounting period.

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The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.

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Net of tax amount of the appreciation (loss) in the value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) losses.

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Net of tax and reclassifications amount of pension and other postretirement benefit plans (gain) loss included in accumulated other comprehensive income (loss).

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