Parent Company (Statements of Cash Flows) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Statements, Captions [Line Items]
Net income	$ 12,125us-gaap_NetIncomeLoss	$ 15,131us-gaap_NetIncomeLoss	$ 15,194us-gaap_NetIncomeLoss
Net change in other assets	790	(1,635)	(2,333)
Net change in other liabilities	(861)	634	(11,282)
Net cash provided by operating activities	15,915	22,564	5,662
Sale of treasury stock	0us-gaap_ProceedsFromSaleOfTreasuryStock	15us-gaap_ProceedsFromSaleOfTreasuryStock	18us-gaap_ProceedsFromSaleOfTreasuryStock
Proceeds from exercise of stock options	225	0	280
Tax benefit from exercise of stock options and distribution of shares in deferred compensation arrangements	14	8	20
Cash dividends paid	(7,085)us-gaap_PaymentsOfDividendsCommonStock	(6,432)us-gaap_PaymentsOfDividendsCommonStock	(6,324)us-gaap_PaymentsOfDividendsCommonStock
Net cash provided by financing activities	(13,665)	9,038	92,321
Increase (decrease) in cash and cash equivalents	38,988	38,243	39,416
Cash and cash equivalents beginning of period	115,471	77,228	37,812
Cash and cash equivalents end of period	154,459	115,471	77,228
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Net income	12,125	15,131	15,194
Net change in other assets	138	65	170
Net change in other liabilities	(67)	(121)	(116)
Equity in undistributed earnings of subsidiaries	(5,857)	(10,211)	(8,721)
Net cash provided by operating activities	6,339	4,864	6,527
Sale of treasury stock	0	15	18
Proceeds from exercise of stock options	0	0	280
Tax benefit from exercise of stock options and distribution of shares in deferred compensation arrangements	14	8	20
Cash dividends paid	(7,167)	(6,432)	(6,324)
Other, net	214	226	200
Net cash provided by financing activities	(6,939)	(6,183)	(5,806)
Increase (decrease) in cash and cash equivalents	(600)	(1,319)	721
Cash and cash equivalents beginning of period	2,797	4,116	3,395
Cash and cash equivalents end of period	$ 2,197	$ 2,797	$ 4,116

Equity in undistributed earnings of subsidiaries.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of deferred tax expense from write-off of the deferred tax asset related to deductible stock options at exercise.

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Other cash or noncash adjustments to reconcile net income to cash provided by (used in) operating activities that are not separately disclosed in the statement of cash flows (for example, cash received or cash paid during the current period for miscellaneous operating activities, net change during the reporting period in other assets or other liabilities).

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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