PORTFOLIO LOANS - Summary of risk grades segregated by category of portfolio loans (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	$ 7,725,702	$ 7,188,998
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	6,964,678	6,518,101
Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	563,897	463,053
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	91,405	121,120
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	90,655	70,778
Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	15,067	15,946
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	1,974,154	1,943,886
Commercial | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	1,668,495	1,747,756
Commercial | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	201,758	93,582
Commercial | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	46,540	69,427
Commercial | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	51,187	26,117
Commercial | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	6,174	7,004
Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	3,261,873	3,119,807
Commercial real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	2,851,709	2,682,441
Commercial real estate | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	326,455	343,304
Commercial real estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	43,526	49,695
Commercial real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	34,539	38,394
Commercial real estate | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	5,644	5,973
Real estate construction
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	530,469	385,996
Real estate construction | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	502,904	369,797
Real estate construction | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	25,164	13,793
Real estate construction | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	1	6
Real estate construction | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	2,400	2,400
Real estate construction | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	0	0
Retail real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	1,657,082	1,512,976
Retail real estate | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	1,639,599	1,491,845
Retail real estate | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	10,520	12,374
Retail real estate | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	1,338	1,992
Retail real estate | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	2,529	3,867
Retail real estate | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	3,096	2,898
Retail other
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	302,124	226,333
Retail other | Pass
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	301,971	226,262
Retail other | Watch
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	0	0
Retail other | Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	0	0
Retail other | Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	0	0
Retail other | Substandard Non-accrual
Financing Receivable, Credit Quality Indicator [Line Items]
Portfolio loans	$ 153	$ 71