INVESTMENT SECURITIES (Schedule of Available for Sale and Held to Maturity Securities with Continuous Unrealized Losses and Approximate Fair Value of Investments) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Available for Sale Securities, Fair Value
Less Than 12 Months	$ 530,647	$ 216,829
12 Months or Longer	73,051	16,009
Total	603,698	232,838
Available for Sale Securities, Unrealized Losses
Less Than 12 Months	(14,478)	(1,428)
12 Months or Longer	(2,383)	(47)
Total	(16,861)	(1,475)
Held to Maturity Securities, Fair Value
Less Than 12 Months	73,282
12 Months or Longer	0
Total	73,282
Held to Maturity Securities, Unrealized Losses
Less Than 12 Months	(294)
12 Months or Longer	0
Total	(294)
Approximate Fair Value
Fair Value, Less than 12 months	603,929
Fair Value, 12 months or longer	73,051
Fair Value	676,980
Unrealized Losses
Unrealized Losses, Less than 12 months	(14,772)
Unrealized Losses, 12 months or longer	(2,383)
Unrealized Losses	(17,155)
12 Months or Longer	73,051	16,009
Total	603,698	232,838
U.S. Government-Sponsored Agencies [Member]
Available for Sale Securities, Fair Value
Less Than 12 Months	243,187	73,769
12 Months or Longer	29,034	0
Total	272,221	73,769
Available for Sale Securities, Unrealized Losses
Less Than 12 Months	(6,858)	(655)
12 Months or Longer	(966)	0
Total	(7,824)	(655)
Held to Maturity Securities, Fair Value
Less Than 12 Months	24,975
12 Months or Longer	0
Total	24,975
Held to Maturity Securities, Unrealized Losses
Less Than 12 Months	(25)
12 Months or Longer	0
Total	(25)
Unrealized Losses
12 Months or Longer	29,034	0
Total	272,221	73,769
Mortgage-Backed Securities-Residential [Member]
Available for Sale Securities, Fair Value
Less Than 12 Months	265,403	103,340
12 Months or Longer	33,455	13,914
Total	298,858	117,254
Available for Sale Securities, Unrealized Losses
Less Than 12 Months	(7,053)	(430)
12 Months or Longer	(884)	(31)
Total	(7,937)	(461)
Held to Maturity Securities, Fair Value
Less Than 12 Months	48,307
12 Months or Longer	0
Total	48,307
Held to Maturity Securities, Unrealized Losses
Less Than 12 Months	(269)
12 Months or Longer	0
Total	(269)
Unrealized Losses
12 Months or Longer	33,455	13,914
Total	298,858	117,254
SBA Pool Securities [Member]
Available for Sale Securities, Fair Value
Less Than 12 Months	22,057	39,720
12 Months or Longer	10,562	2,095
Total	32,619	41,815
Available for Sale Securities, Unrealized Losses
Less Than 12 Months	(567)	(343)
12 Months or Longer	(533)	(16)
Total	(1,100)	(359)
Unrealized Losses
12 Months or Longer	10,562	2,095
Total	$ 32,619	$ 41,815

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