INVESTMENT SECURITIES AVAILABLE FOR SALE (Schedule of Amortized Cost and Approximate Fair Value of Securities Available for Sale) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 850,634	$ 615,396
Gross Unrealized Gains	5,847	8,768
Gross Unrealized Losses	(12,702)	(1,475)
Fair Value	843,779	622,689
U.S. Government-Sponsored Agencies [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	280,102	84,424
Gross Unrealized Gains	0	2
Gross Unrealized Losses	(5,669)	(655)
Fair Value	274,433	83,771
Mortgage-Backed Securities-Residential [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	515,651	467,915
Gross Unrealized Gains	5,663	8,604
Gross Unrealized Losses	(6,183)	(461)
Fair Value	515,131	476,058
SBA Pool Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	43,685	49,457
Gross Unrealized Gains	95	31
Gross Unrealized Losses	(850)	(359)
Fair Value	42,930	49,129
State and Political Subdivisions [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	5,696	7,987
Gross Unrealized Gains	54	102
Gross Unrealized Losses	0	0
Fair Value	5,750	8,089
Corporate Bond [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	5,500	3,000
Gross Unrealized Gains	35	29
Gross Unrealized Losses	0	0
Fair Value	$ 5,535	3,029
U.S. Treasuries [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost		2,613
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Fair Value		$ 2,613

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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Amortized cost of 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 of 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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