Securities (Reconciliation of fair value of securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	$ 378,022	$ 365,140
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	12,996	5,252
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(1,194)	(3,143)
Available-for-sale Securities	389,824	367,249
Held to maturity Securities, Amortized Cost	438,656	477,507
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	13,710	5,177
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	(446)	(3,935)
Held to Maturity, Fair Value, Total	451,920	478,749
Amortized Cost	816,678	842,647
Gross Unrealized Gains	26,706	10,429
Unrealized Losses Other	(1,640)	(7,078)
Fair Value	841,744	845,998
U. S. Government Agency Securities [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	26,988	29,958
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	953	261
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	(4)
Available-for-sale Securities	27,941	30,215
U.S. Treasury securities
Reconciliation of fair value of securities
Held to maturity Securities, Amortized Cost	1,008	1,009
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	92	55
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	0
Held to Maturity, Fair Value, Total	1,100	1,064
Agency mortgage-backed securities
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	186,221	207,693
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	8,230	4,227
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(3)	(983)
Available-for-sale Securities	194,448	210,937
Held to maturity Securities, Amortized Cost	155,468	167,134
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	6,974	3,460
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	(219)
Held to Maturity, Fair Value, Total	162,442	170,375
Agency Collateralized Mortgage Obligations [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	102,381	64,157
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	1,712	179
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(123)	(752)
Available-for-sale Securities	103,970	63,584
Held to maturity Securities, Amortized Cost	247,313	267,348
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	5,316	1,195
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	(446)	(3,652)
Held to Maturity, Fair Value, Total	252,183	264,891
State, County, and Municipal Securities [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	4,267	4,543
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	129	116
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Available-for-sale Securities	4,396	4,659
Held to maturity Securities, Amortized Cost	0	225
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	0	2
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	0
Held to Maturity, Fair Value, Total	0	227
Single Issuer Trust Preferred Securities Issued by Banks and Insurers [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	2,337	2,865
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	5	8
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(78)	(81)
Available-for-sale Securities	2,264	2,792
Held to maturity Securities, Amortized Cost	1,500	1,500
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	46	22
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	0
Held to Maturity, Fair Value, Total	1,546	1,522
Pooled trust preferred securities issued by banks and insurers
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	2,209	2,217
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	0	0
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(703)	(645)
Available-for-sale Securities	1,506	1,572
Small Business Administration Pooled Securities [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	39,252	40,472
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	1,212	87
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	(110)
Available-for-sale Securities	40,464	40,449
Held to maturity Securities, Amortized Cost	33,367	35,291
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	1,282	437
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	(64)
Held to Maturity, Fair Value, Total	34,649	35,664
Equity securities
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	14,367	13,235
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	755	374
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(287)	(568)
Available-for-sale Securities	14,835	13,041
Corporate debt securities
Reconciliation of fair value of securities
Held to maturity Securities, Amortized Cost	0	5,000
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	0	6
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	0
Held to Maturity, Fair Value, Total	$ 0	$ 5,006

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

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

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