LOANS - Narrative (Details) - USD ($)		3 Months Ended												12 Months Ended
	Aug. 01, 2022	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest receivable		$ 18,000,000				$ 16,400,000								$ 18,000,000	$ 16,400,000
Amortized cost, PCD loans		24,000,000				8,600,000								24,000,000	8,600,000
PCD loans, estimated ACL		1,700,000				855,000								1,700,000	855,000
Interest income not recorded due to loans in non-accrual status																$ 1,500,000
Nonaccrual		10,430,000				23,418,000				$ 0				10,430,000	23,418,000	0
Total		21,751,000				24,158,000				27,500,000				21,751,000	24,158,000	27,500,000
Additional amount committed on TDR loans		0												0
TDRs allowance for loan losses														841,000	4,300,000	4,100,000
TDR's period increase, allowance for loans losses														22,000	1,600,000	127,000
Troubled debt restructuring, charge-offs		0				0				0				0	0	0
TDRs subsequent default, period increase in allowance														22,000	21,000	81,000
Total loans, other financial institutions		202,600,000				118,400,000								202,600,000	118,400,000
Loans sold to other financial institutions.		100,100,000				77,800,000								100,100,000	77,800,000
Loan purchased by other financial institutions.		102,500,000				40,600,000								$ 102,500,000	40,600,000
LGD interest rate														15.00%
Threshold default percentage														1.00%
Provision for credit losses, LHFI														$ 5,350,000	(1,456,000)	25,151,000
Provision for credit losses		705,000	$ 4,300,000	$ 600,000	$ 0	$ (1,104,000)	$ 0	$ 0	$ 0	$ 3,522,000	$ 6,921,000	$ 7,606,000	$ 7,102,000	5,605,000	(1,104,000)	$ 25,151,000
Initial allowance on PCD loans		1,303,000												1,303,000
Cadence Bank, N.A
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provision for credit losses, LHFI															370,000
Provision for credit losses														370,000	$ 370,000
Beach Bancorp
Accounts, Notes, Loans and Financing Receivable [Line Items]
Business combination, acquired receivable, fair value	$ 460,000,000
Financing receivable, excluding accrued interest, discount (premium)	8,800,000
Business combination, acquired receivables, gross contractual amount	468,800,000
Business combination, acquired receivables, estimated uncollectible	6,400,000
Provision for credit losses	$ 1,300,000													3,900,000
Initial allowance on PCD loans		$ 1,300,000												$ 1,300,000