Securities (Summary of Investments) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	$ 373,376	$ 351,068
Available for sale securities unrealized gains	7,203	11,630
Available for sale securities unrealized losses	(5,535)	(5,036)
Available for sale, at fair value	375,044	357,662
Held to maturity securities amortized cost	20,023	25,222
Held to maturity securities unrealized gains	493	786
Held to Matruity securities unrealized losses	0	0
Held to maturity securities fair value	20,516	26,008
Total securities amortized cost	393,399	376,290
Total securities unrealized gains	7,696	12,416
Total securities unrealized losses	(5,535)	(5,036)
Total securities fair value	395,560	383,670
Available for sale securities amortized cost	373,376
Obligations of U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	77,330	31,205
Available for sale securities unrealized gains	73	21
Available for sale securities unrealized losses	(388)	(54)
Available for sale, at fair value	77,015	31,172
Available for sale securities amortized cost	77,330
Mortgage-backed securities issued by U.S. government-sponsored agencies and U.S. government-sponsored enterprises [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	228,908	235,343
Available for sale securities unrealized gains	6,398	10,023
Available for sale securities unrealized losses	(450)	0
Available for sale, at fair value	234,856	245,366
Held to maturity securities amortized cost	20,023	25,222
Held to maturity securities unrealized gains	493	786
Held to Matruity securities unrealized losses	0	0
Held to maturity securities fair value	20,516	26,008
Available for sale securities amortized cost	228,908
Obligations of states and political subdivisions [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	35,353	47,647
Available for sale securities unrealized gains	727	1,529
Available for sale securities unrealized losses	0	0
Available for sale, at fair value	36,080	49,176
Available for sale securities amortized cost	35,353
Individual name issuer trust preferred debt securities [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	29,815	30,753
Available for sale securities unrealized gains	0	0
Available for sale securities unrealized losses	(4,677)	(4,979)
Available for sale, at fair value	25,138	25,774
Available for sale securities amortized cost	29,815
Corporate bonds [Member]
Schedule of Available for Sale and Held to Maturity Securities [Line Items]
Available for sale securities amortized cost	1,970	6,120
Available for sale securities unrealized gains	5	57
Available for sale securities unrealized losses	(20)	(3)
Available for sale, at fair value	1,955	$ 6,174
Available for sale securities amortized cost	$ 1,970

This item represents the cost of debt 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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