LOANS - Risk Rating (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Loans by risk rating
Total loans	$ 3,515,831	$ 3,171,558
Commercial
Loans by risk rating
Total loans	2,072,153	1,628,601
Commercial real estate | Commercial
Loans by risk rating
Total loans	1,380,071	1,168,412
Commercial real estate | Commercial | Loans rated 1 - 6, pass
Loans by risk rating
Total loans	1,352,794	1,163,343
Commercial real estate | Commercial | Loans rated 7, special mention
Loans by risk rating
Total loans	23,646	4,539
Commercial real estate | Commercial | Loans rated 8, substandard
Loans by risk rating
Total loans	524	530
Commercial real estate | Commercial | Loans rated 9, doubtful
Loans by risk rating
Total loans	3,107
Commercial construction | Commercial
Loans by risk rating
Total loans	211,953	153,907
Commercial construction | Commercial | Loans rated 1 - 6, pass
Loans by risk rating
Total loans	201,014	127,962
Commercial construction | Commercial | Loans rated 7, special mention
Loans by risk rating
Total loans		14,701
Commercial construction | Commercial | Loans rated 8, substandard
Loans by risk rating
Total loans	10,939	11,244
Commercial and industrial | Commercial
Loans by risk rating
Total loans	480,129	306,282
Commercial and industrial | Commercial | Loans rated 1 - 6, pass
Loans by risk rating
Total loans	466,254	294,507
Commercial and industrial | Commercial | Loans rated 7, special mention
Loans by risk rating
Total loans	3,519	6,117
Commercial and industrial | Commercial | Loans rated 8, substandard
Loans by risk rating
Total loans	8,342	3,223
Commercial and industrial | Commercial | Loans rated 9, doubtful
Loans by risk rating
Total loans	$ 2,014	$ 2,435