Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 1,567,827	$ 1,415,959
Gross Unrealized Gains	995	25,455
Gross Unrealized Losses	(207,140)	(13,737)
Fair Value	1,361,682	1,427,677
U.S. Treasury and U.S. government sponsored entities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	112,703	93,137
Gross Unrealized Gains	0	32
Gross Unrealized Losses	(13,530)	(2,338)
Fair Value	99,173	90,831
State and political subdivisions
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	687,506	636,724
Gross Unrealized Gains	958	23,296
Gross Unrealized Losses	(100,107)	(1,205)
Fair Value	588,357	658,815
Mortgage-backed securities - residential
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	703,946	663,405
Gross Unrealized Gains	25	1,875
Gross Unrealized Losses	(90,663)	(10,094)
Fair Value	613,308	655,186
Collateralized mortgage obligations - residential
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	54,653	13,303
Gross Unrealized Gains	11	153
Gross Unrealized Losses	(2,388)	(71)
Fair Value	52,276	13,385
Corporate bonds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	4,392	4,009
Gross Unrealized Gains	1	50
Gross Unrealized Losses	(186)	(29)
Fair Value	4,207	4,030
Small Business Administration
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	4,627	5,381
Gross Unrealized Gains	0	49
Gross Unrealized Losses	(266)	0
Fair Value	$ 4,361	$ 5,430

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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