SECURITIES - Summary of Available-For-Sale Securities With Unrealized and Unrecognized Losses (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Debt and Equity Securities, FV-NI [Line Items]
Fair value, Less than 12 Months	$ 1,263,342	$ 966,502
Fair Value, 12 Months or Longer	127,652	20,938
Fair Value, Total	1,390,994	987,440
Unrealized Losses, Less than 12 Months	131,975	10,511
Unrealized Losses, 12 Months or Longer	18,532	585
Unrealized Losses, Total	150,507	11,096
Fair Value, Held-to-maturity, Less than 12 Months	507,957
Fair Value, Held-to-maturity, 12 Months or Longer	0
Fair Value, Held-to-maturity, Total	507,957
Unrealized Losses, Held-to-maturity, Less than 12 Months	32,049
Unrealized Losses, Held-to-maturity, 12 Months or Longer	0
Unrealized Losses, Held-to-maturity, Total	32,049
U.S. Treasury
Debt and Equity Securities, FV-NI [Line Items]
Fair value, Less than 12 Months	124,260	130,098
Fair Value, 12 Months or Longer	2,582	0
Fair Value, Total	126,842	130,098
Unrealized Losses, Less than 12 Months	8,794	814
Unrealized Losses, 12 Months or Longer	185	0
Unrealized Losses, Total	8,979	814
Fair Value, Held-to-maturity, Less than 12 Months	106,124
Fair Value, Held-to-maturity, 12 Months or Longer	0
Fair Value, Held-to-maturity, Total	106,124
Unrealized Losses, Held-to-maturity, Less than 12 Months	3,403
Unrealized Losses, Held-to-maturity, 12 Months or Longer	0
Unrealized Losses, Held-to-maturity, Total	3,403
Obligations of U.S. government agencies and sponsored entities
Debt and Equity Securities, FV-NI [Line Items]
Fair value, Less than 12 Months	152,689	121,402
Fair Value, 12 Months or Longer	4,503	5,254
Fair Value, Total	157,192	126,656
Unrealized Losses, Less than 12 Months	12,837	933
Unrealized Losses, 12 Months or Longer	538	161
Unrealized Losses, Total	13,375	1,094
Fair Value, Held-to-maturity, Less than 12 Months	32,638
Fair Value, Held-to-maturity, 12 Months or Longer	0
Fair Value, Held-to-maturity, Total	32,638
Unrealized Losses, Held-to-maturity, Less than 12 Months	489
Unrealized Losses, Held-to-maturity, 12 Months or Longer	0
Unrealized Losses, Held-to-maturity, Total	489
Tax-exempt and taxable obligations of states and municipal subdivisions
Debt and Equity Securities, FV-NI [Line Items]
Fair value, Less than 12 Months	477,118	249,430
Fair Value, 12 Months or Longer	58,393	3,692
Fair Value, Total	535,511	253,122
Unrealized Losses, Less than 12 Months	70,673	2,692
Unrealized Losses, 12 Months or Longer	9,988	119
Unrealized Losses, Total	80,661	2,811
Fair Value, Held-to-maturity, Less than 12 Months	86,881
Fair Value, Held-to-maturity, 12 Months or Longer	0
Fair Value, Held-to-maturity, Total	86,881
Unrealized Losses, Held-to-maturity, Less than 12 Months	11,576
Unrealized Losses, Held-to-maturity, 12 Months or Longer	0
Unrealized Losses, Held-to-maturity, Total	11,576
Mortgage-backed securities - residential
Debt and Equity Securities, FV-NI [Line Items]
Fair value, Less than 12 Months	299,279	284,183
Fair Value, 12 Months or Longer	31,500	8,912
Fair Value, Total	330,779	293,095
Unrealized Losses, Less than 12 Months	24,606	3,228
Unrealized Losses, 12 Months or Longer	4,595	197
Unrealized Losses, Total	29,201	3,425
Fair Value, Held-to-maturity, Less than 12 Months	153,314
Fair Value, Held-to-maturity, 12 Months or Longer	0
Fair Value, Held-to-maturity, Total	153,314
Unrealized Losses, Held-to-maturity, Less than 12 Months	10,139
Unrealized Losses, Held-to-maturity, 12 Months or Longer	0
Unrealized Losses, Held-to-maturity, Total	10,139
Mortgage-backed securities - commercial
Debt and Equity Securities, FV-NI [Line Items]
Fair value, Less than 12 Months	182,312	174,697
Fair Value, 12 Months or Longer	30,647	3,038
Fair Value, Total	212,959	177,735
Unrealized Losses, Less than 12 Months	13,954	2,836
Unrealized Losses, 12 Months or Longer	3,222	103
Unrealized Losses, Total	17,176	2,939
Fair Value, Held-to-maturity, Less than 12 Months	119,649
Fair Value, Held-to-maturity, 12 Months or Longer	0
Fair Value, Held-to-maturity, Total	119,649
Unrealized Losses, Held-to-maturity, Less than 12 Months	5,793
Unrealized Losses, Held-to-maturity, 12 Months or Longer	0
Unrealized Losses, Held-to-maturity, Total	5,793
Corporate obligations
Debt and Equity Securities, FV-NI [Line Items]
Fair value, Less than 12 Months	27,684	6,692
Fair Value, 12 Months or Longer	27	42
Fair Value, Total	27,711	6,734
Unrealized Losses, Less than 12 Months	1,111	8
Unrealized Losses, 12 Months or Longer	4	5
Unrealized Losses, Total	1,115	$ 13
Fair Value, Held-to-maturity, Less than 12 Months	9,351
Fair Value, Held-to-maturity, 12 Months or Longer	0
Fair Value, Held-to-maturity, Total	9,351
Unrealized Losses, Held-to-maturity, Less than 12 Months	649
Unrealized Losses, Held-to-maturity, 12 Months or Longer	0
Unrealized Losses, Held-to-maturity, Total	$ 649