Securities (Reconciliation of fair value of available for sale securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	$ 20,674	$ 6,118
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(498)	(397)
Debt Securities, Available-for-sale	420,517	426,424
Debt Securities, Available-for-sale, Amortized Cost	400,341	420,703
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	33,030	13,428
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(2)	(971)
Held to Maturity, Fair Value, Total	764,054	753,263
Amortized Cost	1,131,367
U.S. government agency securities
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,870	642
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Debt Securities, Available-for-sale, Allowance for Credit Loss	0
Debt Securities, Available-for-sale	24,345	33,115
Debt Securities, Available-for-sale, Amortized Cost	22,475	32,473
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain		123
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	0
Held to Maturity, Fair Value, Total	0	12,997
U.S. Treasury securities
Reconciliation of fair value of securities
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	94	21
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	0
Held to Maturity, Fair Value, Total	4,119	4,053
Agency mortgage-backed securities
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	11,588	3,456
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(2)	(4)
Debt Securities, Available-for-sale, Allowance for Credit Loss	0
Debt Securities, Available-for-sale	248,805	247,000
Debt Securities, Available-for-sale, Amortized Cost	237,219	243,548
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	21,135	8,445
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	(57)
Held to Maturity, Fair Value, Total	453,036	405,802
Agency Collateralized Mortgage Obligations [Member]
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3,776	1,225
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	(19)
Debt Securities, Available-for-sale, Allowance for Credit Loss	0
Debt Securities, Available-for-sale	80,812	88,511
Debt Securities, Available-for-sale, Amortized Cost	77,036	87,305
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	10,360	4,501
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	(849)
Held to Maturity, Fair Value, Total	275,035	297,314
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	21	19
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Debt Securities, Available-for-sale, Allowance for Credit Loss	0
Debt Securities, Available-for-sale	1,147	1,396
Debt Securities, Available-for-sale, Amortized Cost	1,126	1,377
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 Gain, before Tax		5
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(44)	0
Debt Securities, Available-for-sale, Allowance for Credit Loss	0
Debt Securities, Available-for-sale	445	493
Debt Securities, Available-for-sale, Amortized Cost	489	488
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	0	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(2)	(10)
Held to Maturity, Fair Value, Total	1,498	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	(452)	(374)
Debt Securities, Available-for-sale, Allowance for Credit Loss	0
Debt Securities, Available-for-sale	986	1,114
Debt Securities, Available-for-sale, Amortized Cost	1,438	1,488
Small Business Administration Pooled Securities [Member]
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3,419	771
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Debt Securities, Available-for-sale, Allowance for Credit Loss	0
Debt Securities, Available-for-sale	63,977	54,795
Debt Securities, Available-for-sale, Amortized Cost	60,558	54,024
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	1,441	338
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	(55)
Held to Maturity, Fair Value, Total	$ 30,366	$ 31,607

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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Amount, before tax, of unrealized loss 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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