Accumulated Other Comprehensive Income (Loss) - Reclassifications Out of AOCI (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Securities gains, net	$ 1,378		$ 1		$ 1,394		$ 592
Portion of loss recognized in (transferred from) other comprehensive income (before taxes)	(2,038)		4		(2,038)		4
Income tax expense (benefit)	351		(599)		(761)		(1,111)
Interest expense on junior subordinated debt	(297)		(315)		(580)		(586)
Net income	222		1,753		2,820		3,360
Reclassification out of Accumulated Other Comprehensive Income | Available-for-Sale Securities Without Other-Than-Temporary Impairments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Securities gains, net	1,378	[1]	1	[1]	1,394	[1]	592	[1]
Income tax expense (benefit)	(514)	[1]	0	[1]	(520)	[1]	(220)	[1]
Net income	864	[1]	1	[1]	874	[1]	372	[1]
Reclassification out of Accumulated Other Comprehensive Income | Available-for-Sale Securities With Other-Than-Temporary Impairments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Portion of loss recognized in (transferred from) other comprehensive income (before taxes)	(2,038)	[1]	(4)	[1]	(2,038)	[1]	(4)	[1]
Income tax expense (benefit)	760	[1]	1	[1]	760	[1]	1	[1]
Net income	(1,278)	[1]	(3)	[1]	(1,278)	[1]	(3)	[1]
Reclassification out of Accumulated Other Comprehensive Income | Cash Flow Hedge
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax expense (benefit)	63	[1]	57	[1]	122	[1]	111	[1]
Net income	(108)	[1]	(94)	[1]	(206)	[1]	(186)	[1]
Reclassification out of Accumulated Other Comprehensive Income | Defined Benefit Pension Plan
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Income tax expense (benefit)	221	[1]	199	[1]	441	[1]	398	[1]
Amortization of actuarial loss	(591)	[1],[2]	(534)	[1],[2]	(1,182)	[1],[2]	(1,068)	[1],[2]
Net income	(370)	[1]	(335)	[1]	(741)	[1]	(670)	[1]
Interest Rate Contract | Reclassification out of Accumulated Other Comprehensive Income | Cash Flow Hedge
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense on junior subordinated debt	$ (171)	[1]	$ (151)	[1]	$ (328)	[1]	$ (297)	[1]

[1] Positive amounts are credits/revenues and negative amounts are debits/expenses.

[2] This component is included in the computation of net periodic pension expense (see Note 8, Pension and Other Employee Benefit Plans) which is included in salaries and employee benefits expense.