Securities (Reconciliation of fair value of available for sale securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	$ 19,871	$ 6,118
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(552)	(397)
Debt Securities, Available-for-sale	423,478	426,424
Debt Securities, Available-for-sale, Amortized Cost	404,159	420,703
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	30,896	13,428
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(2)	(971)
Held to Maturity, Fair Value, Total	690,467	753,263
Amortized Cost	1,063,732
U.S. government agency securities
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	1,798	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	24,273	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	79	21
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	0
Held to Maturity, Fair Value, Total	4,100	4,053
Agency mortgage-backed securities
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	10,471	3,456
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(1)	(4)
Debt Securities, Available-for-sale, Allowance for Credit Loss	0
Debt Securities, Available-for-sale	230,620	247,000
Debt Securities, Available-for-sale, Amortized Cost	220,150	243,548
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	19,687	8,445
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	(57)
Held to Maturity, Fair Value, Total	407,793	405,802
Agency Collateralized Mortgage Obligations [Member]
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3,539	1,225
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(119)	(19)
Debt Securities, Available-for-sale, Allowance for Credit Loss	0
Debt Securities, Available-for-sale	102,077	88,511
Debt Securities, Available-for-sale, Amortized Cost	98,657	87,305
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	9,557	4,501
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	(849)
Held to Maturity, Fair Value, Total	246,937	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	20	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	1,145	1,396
Debt Securities, Available-for-sale, Amortized Cost	1,125	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	(20)	0
Debt Securities, Available-for-sale, Allowance for Credit Loss	0
Debt Securities, Available-for-sale	469	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	(412)	(374)
Debt Securities, Available-for-sale, Allowance for Credit Loss	0
Debt Securities, Available-for-sale	1,021	1,114
Debt Securities, Available-for-sale, Amortized Cost	1,433	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	4,043	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	63,873	54,795
Debt Securities, Available-for-sale, Amortized Cost	59,830	54,024
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	1,573	338
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	(55)
Held to Maturity, Fair Value, Total	$ 30,139	$ 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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