LOANS AND ALLOWANCE - Changes in Allowance for Loan Losses by Loan Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 223,052	$ 195,984	$ 223,277	$ 195,397
Provision for credit losses	0	0	0	0
CECL Day 1 non-PCD provision for credit losses		13,955		13,955
CECL Day 1 PCD ACL		16,599		16,599
Recoveries on loans	445	1,169	1,289	2,221
Loans charged off	(2,350)	(1,432)	(3,419)	(1,897)
Ending balance	221,147	226,275	221,147	226,275
Commercial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	101,304	77,637	102,216	69,935
Provision for credit losses	7,639	805	6,440	8,376
CECL Day 1 non-PCD provision for credit losses		2,957		2,957
CECL Day 1 PCD ACL		12,970		12,970
Recoveries on loans	66	569	596	708
Loans charged off	(636)	(710)	(879)	(718)
Ending balance	108,373	94,228	108,373	94,228
Commercial Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	46,308	53,000	46,839	60,665
Provision for credit losses	(7,151)	(6,393)	(7,734)	(14,643)
CECL Day 1 non-PCD provision for credit losses		5,539		5,539
CECL Day 1 PCD ACL		2,981		2,981
Recoveries on loans	0	201	56	908
Loans charged off	0	0	(4)	(122)
Ending balance	39,157	55,328	39,157	55,328
Construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	28,571	20,760	28,955	20,206
Provision for credit losses	1,502	5,122	1,118	5,676
CECL Day 1 non-PCD provision for credit losses		871		871
CECL Day 1 PCD ACL		648		648
Recoveries on loans	0	0	0	0
Loans charged off	0	0	0	0
Ending balance	30,073	27,401	30,073	27,401
Consumer & Residential
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	46,869	44,587	45,267	44,591
Provision for credit losses	(1,990)	466	176	591
CECL Day 1 non-PCD provision for credit losses		4,588		4,588
CECL Day 1 PCD ACL		0		0
Recoveries on loans	379	399	637	605
Loans charged off	(1,714)	(722)	(2,536)	(1,057)
Ending balance	$ 43,544	$ 49,318	$ 43,544	$ 49,318

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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Amount of increase in allowance for credit loss on financing receivable from purchase of loan. Excludes financing receivable purchased with credit deterioration, loan acquired through business combination or acquisition, and net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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-Name Accounting Standards Codification
-Section 50
-Paragraph 13
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-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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Amount of increase in allowance for credit loss on financing receivable purchased with credit deterioration.

+ References

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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-Topic 326
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Amount of credit loss expense (reversal of expense) for financing receivable.

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