Securities (Reconciliation of fair value of securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	$ 376,520	$ 365,140
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	11,583	5,252
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(1,095)	(3,143)
Available-for-sale Securities	387,008	367,249
Held to maturity Securities, Amortized Cost	430,763	477,507
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	11,627	5,177
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	(556)	(3,935)
Held to Maturity, Fair Value, Total	441,834	478,749
Amortized Cost	807,283	842,647
Gross Unrealized Gains	23,210	10,429
Unrealized Losses Other	(1,651)	(7,078)
Fair Value	828,842	845,998
U. S. Government Agency Securities [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	24,502	29,958
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	804	261
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	(4)
Available-for-sale Securities	25,306	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	81	55
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	0
Held to Maturity, Fair Value, Total	1,089	1,064
Agency mortgage-backed securities
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	178,095	207,693
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	7,481	4,227
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(3)	(983)
Available-for-sale Securities	185,573	210,937
Held to maturity Securities, Amortized Cost	148,822	167,134
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	6,309	3,460
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	(219)
Held to Maturity, Fair Value, Total	155,131	170,375
Agency Collateralized Mortgage Obligations [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	107,466	64,157
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	1,286	179
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(156)	(752)
Available-for-sale Securities	108,596	63,584
Held to maturity Securities, Amortized Cost	246,744	267,348
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	4,072	1,195
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	(556)	(3,652)
Held to Maturity, Fair Value, Total	250,260	264,891
State, County, and Municipal Securities [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	4,255	4,543
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	105	116
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Available-for-sale Securities	4,360	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	2,324	2,865
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	4	8
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(31)	(81)
Available-for-sale Securities	2,297	2,792
Held to maturity Securities, Amortized Cost	1,500	1,500
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	47	22
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	0
Held to Maturity, Fair Value, Total	1,547	1,522
Pooled trust preferred securities issued by banks and insurers
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	2,200	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	(662)	(645)
Available-for-sale Securities	1,538	1,572
Small Business Administration Pooled Securities [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	38,678	40,472
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	1,202	87
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	(110)
Available-for-sale Securities	39,880	40,449
Held to maturity Securities, Amortized Cost	32,689	35,291
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	1,118	437
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	(64)
Held to Maturity, Fair Value, Total	33,807	35,664
Equity securities
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	19,000	13,235
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	701	374
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(243)	(568)
Available-for-sale Securities	19,458	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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