Securities (Reconciliation of fair value of securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	$ 6,002	$ 1,233
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(495)	(9,029)
Debt Securities, Available-for-sale	393,148	442,752
Debt Securities, Available-for-sale, Amortized Cost	387,641	450,548
Held to maturity Securities, Amortized Cost	797,359	611,490
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	12,733	2,533
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(1,436)	(10,383)
Held to Maturity, Fair Value, Total	808,656	603,640
Amortized Cost	1,185,000	1,062,038
Gross Unrealized Gains	18,735	3,766
Unrealized Losses Other	(1,931)	(19,412)
Debt Securities, Available-for-sale and Held-to-maturity	1,201,804	1,046,392
U.S. Government agency securities
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	453
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(6)	(439)
Debt Securities, Available-for-sale	32,923	32,038
Debt Securities, Available-for-sale, Amortized Cost	32,476	32,477
Held to maturity Securities, Amortized Cost	12,833	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	130
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	0
Held to Maturity, Fair Value, Total	12,963
U.S. Treasury securities
Reconciliation of fair value of securities
Held to maturity Securities, Amortized Cost	1,003	1,004
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	21	11
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	0
Held to Maturity, Fair Value, Total	1,024	1,015
Agency mortgage-backed securities
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3,024	1,020
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(41)	(3,406)
Debt Securities, Available-for-sale	197,665	220,105
Debt Securities, Available-for-sale, Amortized Cost	194,682	222,491
Held to maturity Securities, Amortized Cost	423,825	252,484
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	7,488	1,548
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(46)	(3,104)
Held to Maturity, Fair Value, Total	431,267	250,928
Agency Collateralized Mortgage Obligations [Member]
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,420	197
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(76)	(3,435)
Debt Securities, Available-for-sale	98,643	134,911
Debt Securities, Available-for-sale, Amortized Cost	97,299	138,149
Held to maturity Securities, Amortized Cost	324,441	332,775
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	4,627	869
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(1,350)	(6,920)
Held to Maturity, Fair Value, Total	327,718	326,724
US States and Political Subdivisions Debt Securities [Member]
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	23	16
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Debt Securities, Available-for-sale	1,738	1,735
Debt Securities, Available-for-sale, Amortized Cost	1,715	1,719
Single Issuer Trust Preferred Securities Issued by Banks and Insurers [Member]
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	(10)
Debt Securities, Available-for-sale	717	707
Debt Securities, Available-for-sale, Amortized Cost	717	717
Held to maturity Securities, Amortized Cost	1,500	1,500
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(10)	(10)
Held to Maturity, Fair Value, Total	1,490	1,490
Pooled trust preferred securities issued by banks and insurers
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(372)	(349)
Debt Securities, Available-for-sale	1,281	1,329
Debt Securities, Available-for-sale, Amortized Cost	1,653	1,678
Small Business Administration Pooled Securities [Member]
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,082	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	(1,390)
Debt Securities, Available-for-sale	60,181	51,927
Debt Securities, Available-for-sale, Amortized Cost	59,099	53,317
Held to maturity Securities, Amortized Cost	33,757	23,727
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	467	105
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(30)	(349)
Held to Maturity, Fair Value, Total	$ 34,194	$ 23,483

Available for sale securities and held to maturity securities amortized cost.

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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