Consolidated Statements of Changes in Stockholders’ Equity (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Purchase Of Common Shares Outstanding [Member] | Treasury Stock [Member]
Number of shares purchased for the Treasury	624,088
Restricted Stock Awards Repurchased To Satisfy Tax Obligations [Member] | Treasury Stock [Member]
Number of shares purchased for the Treasury	29,838	26,443	22,186
Shares Purchased To Fund Options Exercised [Member] | Treasury Stock [Member]
Number of shares purchased for the Treasury	3,794	26,011	24,848
Preferred Stock [Member]
Preferred shares redeemed, shares			70,000
Common Stock [Member]
Number of shares issued upon the exercise of stock options	155,061	37,054	96,742
Shares issued upon vesting of restricted stock unit awards	119,600	87,821	78,598
Number of shares issued			9,330,010
Additional Paid-in Capital [Member]
Preferred shares redeemed, shares			70,000
Number of shares issued upon the exercise of stock options	155,061	74,340	97,642
Shares issued upon vesting of restricted stock unit awards	127,653	103,109	95,779
Number of shares issued			9,330,010
Release of shares from Employee Benefit Trust, shares	144,312	134,124	169,353
Treasury Stock [Member]
Number of shares issued upon the exercise of stock options	23,249	37,266	26,458
Shares issued upon vesting of restricted stock unit awards	8,053	18,583	17,181
Unearned Compensation [Member]
Release of shares from Employee Benefit Trust, shares		168,759	212,314
Retained Earnings [Member]
Number of shares issued upon the exercise of stock options	23,129	74,320	25,558
Shares issued upon vesting of restricted stock unit awards	7,853	3,295
Cash dividends declared and paid on common shares, dividend per share (in Dollars per share)	0.52	0.52	0.52
Cash dividends declared and paid on preferred shares, cumulative preferred dividends			5.00%
Accumulated Other Comprehensive Income (Loss) [Member]
Amortization of prior service costs (credit), taxes (in Dollars)	20	20	(21)
Amortization of net actuarial losses, taxes (in Dollars)	(243)	(140)	(135)
Unrecognized actuarial (losses) gains, taxes (in Dollars)	1,932	513	(178)
Unrecognized prior service credit, taxes (in Dollars)			(512)
Change in net unrealized (losses) gains on securities available for sale, taxes (in Dollars)	(7,706)	(1,810)	(8,231)
Reclassification adjustment for losses (gains) included in net income, taxes (in Dollars)	(692)	(904)	(1,994)