SECURITIES (Reconciliation of amortized cost of held to maturity securities) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-maturity	$ 1,066,818	$ 724,512
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	12,474	28,007
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(15,159)	(342)
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0	0
Fair Value	1,064,133	752,177
Equity Securities, FV-NI, Realized Gain (Loss)	192	14	$ 18
Internal Investment Grade [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-maturity	1,066,818	724,512
US Government Agencies Debt Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-maturity	32,987	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(441)	0
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0	0
Fair Value	32,546
US Treasury Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-maturity	102,560	4,017
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	6	60
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(324)	0
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0	0
Fair Value	102,242	4,077
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-maturity	493,012	356,085
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	8,495	18,036
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(4,271)	0
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0	0
Fair Value	497,236	374,121
Agency collateralized mortgage obligations [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-maturity	415,736	335,993
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	3,232	8,466
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	(10,123)	(340)
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0	0
Fair Value	408,845	344,119
Single issuer trust preferred securities issued by banks [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-maturity	1,500	1,500
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	8	0
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	(2)
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0	0
Fair Value	1,508	1,498
Small Business Administration Pooled Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Debt Securities, Held-to-maturity	21,023	26,917
Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain	733	1,445
Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss	0	0
Debt Securities, Held-to-maturity, Allowance for Credit Loss	0	0
Fair Value	$ 21,756	$ 28,362

Amount of allowance for credit loss for debt security measured at amortized cost (held-to-maturity).

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