Consolidated Statements of Changes in Stockholders’ Equity (Unaudited) (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Issuance upon exercise of stock options, common shares	151,355
Cash dividends declared and paid on common shares, per common share (in Dollars per share)	$ 0.26	$ 0.26
Reclassification adjustment for losses included in net income, taxes (in Dollars)	$ (1,257)
Additional Paid-in Capital [Member]
Award of common shares released from Employee Benefit Trust, common shares	137,346	150,564
Shares issued upon vesting of restricted stock unit awards, common shares	120,014	113,072
Issuance upon exercise of stock options, common shares	96,925	102,540
Treasury Stock [Member] | Outstanding Common Shares Repurchased [Member]
Repurchase of outstanding shares, common shares	806,092	130,900
Treasury Stock [Member] | Shares Repurchased To Fund Options Exercised [Member]
Repurchase of outstanding shares, common shares	112,332	40,866
Treasury Stock [Member] | Shares Repurchased To Satisfy Tax Obligations [Member]
Repurchase of outstanding shares, common shares	49,103	38,121
Treasury Stock [Member]
Shares issued upon vesting of restricted stock unit awards, common shares	176,456	142,022
Issuance upon exercise of stock options, common shares	151,355	113,020
Retained Earnings [Member]
Shares issued upon vesting of restricted stock unit awards, common shares	56,242	28,950
Issuance upon exercise of stock options, common shares	54,160	10,480
Cash dividends declared and paid on common shares, per common share (in Dollars per share)	$ 0.26	$ 0.26
Accumulated Other Comprehensive Income (Loss) [Member]
Change in net unrealized gains (losses) on securities available for sale, tax effect (in Dollars)	14,140	(2,566)
Amortization of actuarial losses, taxes (in Dollars)	(270)	(233)
Amortization of prior service credits, taxes (in Dollars)	10	10
OTTI charges included in income, taxes (in Dollars)	(220)	(339)
Reclassification adjustment for losses included in net income, taxes (in Dollars)	$ 1,257