Securities (Schedule of Securities Available-for-Sale) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 1,172,175	$ 834,850
Gross Unrealized Gains	46,003	21,780
Gross Unrealized Losses	(326)	(1,805)
Fair Value	1,217,852	854,825
Obligations of State and Political Subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	548,273	307,943
Gross Unrealized Gains	33,077	16,366
Gross Unrealized Losses	(103)	(9)
Fair Value	581,247	324,300
MBS/CMO
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	535,526	526,907
Gross Unrealized Gains	12,806	5,414
Gross Unrealized Losses	(25)	(1,796)
Fair Value	548,307	530,525
US Gov't Sponsored Entities & Agencies
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	88,376	0
Gross Unrealized Gains	120	0
Gross Unrealized Losses	(198)	0
Fair Value	$ 88,298	$ 0

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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