Securities (Reconciliation of fair value of available for sale securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	$ 809	$ 8,808
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(95,016)	(21,396)
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale	1,552,731	1,571,148
Debt Securities, Available-for-sale, Amortized Cost	1,646,938	1,583,736
U.S. government agency securities
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	44	990
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(15,594)	(2,901)
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale	215,935	215,482
Debt Securities, Available-for-sale, Amortized Cost	231,485	217,393
U.S. treasury securities
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax		172
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(51,275)	(12,191)
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale	822,333	861,448
Debt Securities, Available-for-sale, Amortized Cost	873,608	873,467
Agency mortgage-backed securities
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	670	4,512
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(24,436)	(5,534)
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale	397,985	363,933
Debt Securities, Available-for-sale, Amortized Cost	421,751	364,955
Agency Collateralized Mortgage Obligations [Member]
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	39	1,282
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(796)	(571)
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale	49,002	79,677
Debt Securities, Available-for-sale, Amortized Cost	49,759	78,966
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	8	11
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale	200	203
Debt Securities, Available-for-sale, Amortized Cost	192	192
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	0	2
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale	489	491
Debt Securities, Available-for-sale, Amortized Cost	489	489
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	(200)	(199)
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale	999	1,000
Debt Securities, Available-for-sale, Amortized Cost	1,199	1,199
Small Business Administration Pooled Securities [Member]
Reconciliation of fair value of securities
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	48	1,839
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	(2,715)	0
Debt Securities, Available-for-sale, Allowance for Credit Loss	0	0
Debt Securities, Available-for-sale	65,788	48,914
Debt Securities, Available-for-sale, Amortized Cost	$ 68,455	$ 47,075

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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