Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Statement of Other Comprehensive Income [Abstract]
Net income	$ 4,921	$ 5,030	$ 9,943	$ 11,687
Available-for-sale investment securities:
Gross unrealized holding gain arising in the period	(16,727)	2,638	(16,270)	1,575
Related tax expense	5,854	(923)	5,694	(551)
Less: reclassification adjustment for net gain included in net income	26	0	444	3,163
Related tax expense on reclassification adjustment	(9)	0	(155)	(1,107)
Net effect on other comprehensive income (loss)	(10,890)	1,715	(10,865)	(1,032)
Defined benefit plans:
Net loss arising during the period	0	(355)	0	(355)
Related tax benefit	0	124	0	124
Amortization of unrecognized loss and service cost on pension plan	52	41	97	79
Related tax expense on amortization	(18)	(14)	(34)	(27)
Recognition of loss due to settlement and curtailment	0	353	0	353
Related tax expense	0	(124)	0	(124)
Net effect on other comprehensive income (loss)	(34)	(25)	(63)	(50)
Total other comprehensive income (loss), net of tax	(10,856)	1,740	(10,802)	(982)
Total comprehensive income	$ (5,935)	$ 6,770	$ (859)	$ 10,705

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The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.