Securities (Summary of Investments) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	$ 318,784	$ 387,910
Available for sale securities unrealized gains	12,907	11,520
Available for sale securities unrealized losses	(4,113)	(6,527)
Total securities available for sale fair value	327,578	392,903
Held to maturity securities	27,814	29,905
Held to maturity securities unrealized gains	804	14
Held to maturity securities unrealized losses	0	(54)
Held to maturity securities fair value	28,618	29,865
Total available for sale and held to maturity securities amortized cost	346,598	417,815
Total available for sale and held to maturity securities unrealized gains	13,711	11,534
Total available for sale and held to maturity securities unrealized losses	(4,113)	(6,581)
Total available for sale and held to maturity securities fair value	356,196	422,768
Obligations of U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	9,999	54,474
Available for sale securities unrealized gains	13	720
Available for sale securities unrealized losses	0	(79)
Total securities available for sale fair value	10,012	55,115
Mortgage-backed securities issued by US Government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	217,767	230,387
Available for sale securities unrealized gains	10,531	8,369
Available for sale securities unrealized losses	(13)	(401)
Total securities available for sale fair value	228,285	238,355
Held to maturity securities	27,814	29,905
Held to maturity securities unrealized gains	804	14
Held to maturity securities unrealized losses	0	(54)
Held to maturity securities fair value	28,618	29,865
Obligations of states and political subdivisions [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	54,161	60,659
Available for sale securities unrealized gains	2,230	2,200
Available for sale securities unrealized losses	0	0
Total securities available for sale fair value	56,391	62,859
Trust preferred securities: Individual name issuers [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	30,734	30,715
Available for sale securities unrealized gains	0	0
Available for sale securities unrealized losses	(4,099)	(6,031)
Total securities available for sale fair value	26,635	24,684
Trust preferred securities: Collateralized debt obligations [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis		547
Available for sale securities unrealized gains		0
Available for sale securities unrealized losses		0
Total securities available for sale fair value		547
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturty Securities [Line Items]
Available for sale securities amortized cost basis	6,123	11,128
Available for sale securities unrealized gains	133	231
Available for sale securities unrealized losses	(1)	(16)
Total securities available for sale fair value	$ 6,255	$ 11,343