Securities (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Securities available for sale
Securities available for sale, amortized cost	$ 465,031		$ 509,276
Unrealized gains	7,726		5,829
Unrealized losses	1,055		2,049
Total securities available-for-sale, fair value	471,702us-gaap_AvailableForSaleSecurities		513,056us-gaap_AvailableForSaleSecurities
Held to maturity securities	0us-gaap_HeldToMaturitySecurities		0us-gaap_HeldToMaturitySecurities
Securities available-for-sale sold	5,934	0
Loss on available-for-sale securities sold	0
U.S. Treasury and other U.S. government obligations
Securities available for sale
Securities available for sale, amortized cost	60		70,000
Total securities available-for-sale, fair value	60		70,000
Government sponsored enterprise obligations
Securities available for sale
Securities available for sale, amortized cost	173,137		203,531
Unrealized gains	2,928		2,017
Unrealized losses	251		562
Total securities available-for-sale, fair value	175,814		204,986
Mortgage-backed securities - government agencies
Securities available for sale
Securities available for sale, amortized cost	167,768		173,573
Unrealized gains	2,872		2,042
Unrealized losses	745		1,345
Total securities available-for-sale, fair value	169,895		174,270
Obligations of states and political subdivisions
Securities available for sale
Securities available for sale, amortized cost	63,370		61,416
Unrealized gains	1,668		1,560
Unrealized losses	59		142
Total securities available-for-sale, fair value	64,979		62,834
Common stock
Securities available for sale
Securities available for sale, amortized cost	756		756
Unrealized gains	258		210
Total securities available-for-sale, fair value	$ 1,014		$ 966

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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