Accumulated Other Comprehensive (Loss) Income - Amounts Reclassified Out of Each Component of Accumulated Comprehensive (Loss) Income (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Net unrealized holding losses on available-for-sale investment securities
Net gain on sales of investment securities	$ 185	$ 258
Other-than-temporary impairment on equity securities		(3)
Total before tax	185	255
Tax expense	(65)	(89)
Net of tax	120	166
Defined benefit pension plans:
Amortization of net loss included in net periodic pension costs	292	297
Accretion of prior service cost included in net periodic pension costs	(64)	(64)
Total before tax	228	233
Tax expense	79	81
Net of tax	$ 149	$ 152