Securities (Reconciliation of fair value of securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	$ 413,496	$ 363,366
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	4,948	3,890
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(2,501)	(3,612)
Available-for-sale Securities	415,943	363,644
Held to maturity Securities, Amortized Cost	498,392	487,076
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	4,121	3,556
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	(3,454)	(4,982)
Held to Maturity, Fair Value, Total	499,059	485,650
Amortized Cost	911,888	850,442
Gross Unrealized Gains	9,069	7,446
Unrealized Losses Other	(5,955)	(8,594)
Fair Value	915,002	849,294
U. S. Government Agency Securities [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	24,009	24,006
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	269	238
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Available-for-sale Securities	24,278	24,244
U.S. Treasury securities
Reconciliation of fair value of securities
Held to maturity Securities, Amortized Cost	1,006	1,007
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	46	47
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	0
Held to Maturity, Fair Value, Total	1,052	1,054
Agency mortgage-backed securities
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	189,780	173,268
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	3,065	2,852
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(175)	(736)
Available-for-sale Securities	192,670	175,384
Held to maturity Securities, Amortized Cost	178,358	156,088
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	2,506	2,274
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	(416)	(858)
Held to Maturity, Fair Value, Total	180,448	157,504
Agency Collateralized Mortgage Obligations [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	121,292	101,094
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	433	106
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(1,028)	(1,332)
Available-for-sale Securities	120,697	99,868
Held to maturity Securities, Amortized Cost	288,428	297,445
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	1,285	1,002
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	(2,881)	(3,797)
Held to Maturity, Fair Value, Total	286,832	294,650
State, County, and Municipal Securities [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	3,723	3,743
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	52	50
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Available-for-sale Securities	3,775	3,793
Single Issuer Trust Preferred Securities Issued by Banks and Insurers [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	2,285	2,311
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	43	3
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	0	(3)
Available-for-sale Securities	2,328	2,311
Held to maturity Securities, Amortized Cost	1,500	1,500
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	37	44
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	0	0
Held to Maturity, Fair Value, Total	1,537	1,544
Pooled trust preferred securities issued by banks and insurers
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	2,202	2,200
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	0	0
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(609)	(616)
Available-for-sale Securities	1,593	1,584
Small Business Administration Pooled Securities [Member]
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	51,044	37,561
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	0	0
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(265)	(372)
Available-for-sale Securities	50,779	37,189
Held to maturity Securities, Amortized Cost	29,100	31,036
Held-to-maturity Securities, Accumulated Unrecognized Holding Gain	247	189
Held-to-maturity Securities, Accumulated Unrecognized Holding Loss	(157)	(327)
Held to Maturity, Fair Value, Total	29,190	30,898
Equity securities
Reconciliation of fair value of securities
Available for sale Securities, Amortized Cost	19,161	19,183
Available-for-sale Debt Securities, Accumulated Gross Unrealized Gain, before Tax	1,086	641
Available-for-sale Debt Securities, Accumulated Gross Unrealized Loss, before Tax	(424)	(553)
Available-for-sale Securities	$ 19,823	$ 19,271

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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 before tax of unrealized loss 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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