SECURITIES - Summary of Amortized Cost and Fair Value of Available-For-Sale Securities and Held-To-Maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, AFS	$ 1,418,337	$ 1,741,153
Gross unrealized gains, AFS	672	21,775
Total investment securities available-for-sale	1,257,101	1,751,832
Gross unrealized losses, AFS	161,908	11,096
Amortized cost, HTM	691,484	0
Gross unrealized gains, HTM	4,532
Gross unrealized losses, HTM	53,919
Debt securities, HTM, fair value	642,097	0
U.S Treasury
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, AFS	135,752	135,889
Gross unrealized gains, AFS	0	83
Total investment securities available-for-sale	123,854	135,158
Gross unrealized losses, AFS	11,898	814
Amortized cost, HTM	109,631
Gross unrealized gains, HTM	0
Gross unrealized losses, HTM	5,175
Debt securities, HTM, fair value	104,456
Obligations of U.S. government agencies and sponsored entities
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, AFS	163,054	182,877
Gross unrealized gains, AFS	3	1,238
Total investment securities available-for-sale	144,369	183,021
Gross unrealized losses, AFS	18,688	1,094
Amortized cost, HTM	33,789
Gross unrealized gains, HTM	0
Gross unrealized losses, HTM	2,153
Debt securities, HTM, fair value	31,636
Tax-exempt and taxable obligations of states and municipal subdivisions
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, AFS	519,190	698,861
Gross unrealized gains, AFS	598	12,452
Total investment securities available-for-sale	457,857	708,502
Gross unrealized losses, AFS	61,931	2,811
Amortized cost, HTM	247,467
Gross unrealized gains, HTM	4,525
Gross unrealized losses, HTM	13,699
Debt securities, HTM, fair value	238,293
Mortgage-backed securities - residential
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, AFS	341,272	410,269
Gross unrealized gains, AFS	11	4,123
Total investment securities available-for-sale	299,242	410,967
Gross unrealized losses, AFS	42,041	3,425
Amortized cost, HTM	156,119
Gross unrealized gains, HTM	0
Gross unrealized losses, HTM	17,479
Debt securities, HTM, fair value	138,640
Mortgage-backed securities - commercial
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, AFS	215,200	277,353
Gross unrealized gains, AFS	60	2,917
Total investment securities available-for-sale	190,897	277,331
Gross unrealized losses, AFS	24,363	2,939
Amortized cost, HTM	134,478
Gross unrealized gains, HTM	7
Gross unrealized losses, HTM	13,798
Debt securities, HTM, fair value	120,687
Corporate obligations
Debt and Equity Securities, FV-NI [Line Items]
Amortized cost, AFS	43,869	35,904
Gross unrealized gains, AFS	0	962
Total investment securities available-for-sale	40,882	36,853
Gross unrealized losses, AFS	2,987	$ 13
Amortized cost, HTM	10,000
Gross unrealized gains, HTM	0
Gross unrealized losses, HTM	1,615
Debt securities, HTM, fair value	$ 8,385

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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-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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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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Amount excluding accrued interest, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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