Consolidated Statements of Changes in Stockholders’ Equity (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Number of shares issued upon the exercise of stock options	150,115
Number of shares purchased for the Treasury	914,671us-gaap_TreasuryStockSharesAcquired	836,092us-gaap_TreasuryStockSharesAcquired
Amortization of prior service costs (credit), taxes (in Dollars)	$ (311)	$ 521	$ 436
Additional Paid-in Capital [Member]
Release of shares from Employee Benefit Trust, shares	136,559	143,941	157,922
Shares issued upon vesting of restricted stock unit awards	7,300	120,114	113,272
Number of shares issued upon the exercise of stock options	138,575	463,245	125,405
Treasury Stock [Member] \| Shares Purchased To Fund Options Exercised [Member]
Number of shares purchased for the Treasury	97,518	366,517	65,074
Treasury Stock [Member]
Shares issued upon vesting of restricted stock unit awards	202,466	180,997	146,149
Number of shares issued upon the exercise of stock options	150,115	463,245	150,225
Retained Earnings [Member]
Shares issued upon vesting of restricted stock unit awards	195,166	60,883	32,877
Number of shares issued upon the exercise of stock options	11,540	65,470	24,820
Cash dividends declared and paid on preferred shares, cumulative preferred dividends (in Dollars per share)	$ 0.60	$ 0.52	$ 0.52
Accumulated Other Comprehensive Income (Loss) [Member]
Amortization of prior service costs (credit), taxes (in Dollars)	19	20	20
Amortization of net actuarial losses, taxes (in Dollars)	(330)	(541)	(456)
Unrecognized actuarial (losses) gains, taxes (in Dollars)	2,880	(2,527)	340
Change in net unrealized gains on securities available for sale, taxes (in Dollars)	(10,441)	20,609	(5,259)
Reclassification adjustment for losses (gains) included in net income, taxes (in Dollars)	$ 1,241	$ 700	$ (318)
Purchase of Common Shares Outstanding [Member]
Number of shares purchased for the Treasury	914,671	836,092	352,000
Restricted Stock Awards Repurchased To Satisfy Tax Obligations [Member]
Number of shares purchased for the Treasury	59,821	61,710	40,148

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