Investment Securities - Unrealized losses (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities
Less than 12 Months, Fair Value	$ 80,631	$ 249,957
12 Months or More, Fair Value	48,027	35,182
Total Fair Value	128,658	285,139
Less than 12 Months, Unrealized Losses	(702)	(7,236)
12 Months or More, Unrealized Losses	(645)	(1,793)
Total Unrealized Losses	(1,347)	(9,029)
U.S. Government agencies
Schedule of Available-for-sale Securities
Less than 12 Months, Fair Value	10,950	4,132
12 Months or More, Fair Value	1,737	968
Total Fair Value	12,687	5,100
Less than 12 Months, Unrealized Losses	(193)	(75)
12 Months or More, Unrealized Losses	(50)	(9)
Total Unrealized Losses	(243)	(84)
Obligations of states and political subdivisions
Schedule of Available-for-sale Securities
Less than 12 Months, Fair Value	16,776	89,556
12 Months or More, Fair Value	15,290	15,015
Total Fair Value	32,066	104,571
Less than 12 Months, Unrealized Losses	(89)	(5,007)
12 Months or More, Unrealized Losses	(225)	(1,510)
Total Unrealized Losses	(314)	(6,517)
Held-to-maturity Securities
Held-to-maturity Securities, Less than 12 Months, Fair Value	1,067
Held-to-maturity Securities, 12 Months or More, Fair Value	0
Held-to-maturity Securities, Total Fair Value	1,067
Held-to-maturity Securities, Less than 12 Months, Unrealized Losses	(6)
Held-to-maturity Securities, 12 Months or More,Unrealized Losses	0
Held-to-maturity Securities, Total Unrealized Losses	(6)
U.S. Government agencies collateralized by residential mortgage obligations
Schedule of Available-for-sale Securities
Less than 12 Months, Fair Value	52,905	148,853
12 Months or More, Fair Value	31,000	19,199
Total Fair Value	83,905	168,052
Less than 12 Months, Unrealized Losses	(420)	(2,070)
12 Months or More, Unrealized Losses	(370)	(274)
Total Unrealized Losses	(790)	(2,344)
Other equity securities
Schedule of Available-for-sale Securities
Less than 12 Months, Fair Value		7,416
12 Months or More, Fair Value		0
Total Fair Value		7,416
Less than 12 Months, Unrealized Losses		(84)
12 Months or More, Unrealized Losses		0
Total Unrealized Losses		$ (84)

Amount of unrealized loss on securities classified as available-for-sale that have been in a loss position for twelve months or longer.

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Amount of unrealized loss on investments in available-for-sale securities that have been in a loss position for less than twelve months.

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