Consolidated Balance Sheets (Parentheticals) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Statement of Financial Position [Abstract]
Available for sale securities, amortized cost	$ 592,005	$ 628,584
Held to maturity securities, fair value	$ 48,567	$ 47,124
Preferred stock, shares authorized	50,000	50,000
Preferred stock, shares issued	0	0
Common stock, shares authorized	24,000,000	24,000,000
Common stock, shares issued	11,167,721	11,155,648
Treasury stock, shares	599,574	607,688

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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