LOANS - Categorized by Class and Internally Assigned Risk Grades (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Loans by class categorized by internally assigned risk grades
Total loans	$ 3,672,596	$ 3,268,772
Pass
Loans by class categorized by internally assigned risk grades
Total loans	3,584,290	3,180,905
Special Mention
Loans by class categorized by internally assigned risk grades
Total loans	47,003	43,186
Substandard
Loans by class categorized by internally assigned risk grades
Total loans	41,303	44,681
Doubtful
Loans by class categorized by internally assigned risk grades
Total loans	0	0
Commercial Real Estate | Mortgage loans
Loans by class categorized by internally assigned risk grades
Total loans	1,565,687	1,373,556
Commercial Real Estate | Mortgage loans | Owner occupied
Loans by class categorized by internally assigned risk grades
Total loans	531,088	510,398
Commercial Real Estate | Mortgage loans | Owner occupied | Pass
Loans by class categorized by internally assigned risk grades
Total loans	511,444	480,503
Commercial Real Estate | Mortgage loans | Owner occupied | Special Mention
Loans by class categorized by internally assigned risk grades
Total loans	18,426	12,045
Commercial Real Estate | Mortgage loans | Owner occupied | Substandard
Loans by class categorized by internally assigned risk grades
Total loans	1,218	17,850
Commercial Real Estate | Mortgage loans | Owner occupied | Doubtful
Loans by class categorized by internally assigned risk grades
Total loans	0	0
Commercial Real Estate | Mortgage loans | Non-owner occupied
Loans by class categorized by internally assigned risk grades
Total loans	1,034,599	863,158
Commercial Real Estate | Mortgage loans | Non-owner occupied | Pass
Loans by class categorized by internally assigned risk grades
Total loans	1,022,208	858,069
Commercial Real Estate | Mortgage loans | Non-owner occupied | Special Mention
Loans by class categorized by internally assigned risk grades
Total loans	0	2,188
Commercial Real Estate | Mortgage loans | Non-owner occupied | Substandard
Loans by class categorized by internally assigned risk grades
Total loans	12,391	2,901
Commercial Real Estate | Mortgage loans | Non-owner occupied | Doubtful
Loans by class categorized by internally assigned risk grades
Total loans	0	0
Multi-family | Mortgage loans
Loans by class categorized by internally assigned risk grades
Total loans	812,174	585,827
Multi-family | Mortgage loans | Pass
Loans by class categorized by internally assigned risk grades
Total loans	811,770	585,409
Multi-family | Mortgage loans | Special Mention
Loans by class categorized by internally assigned risk grades
Total loans	404	418
Multi-family | Mortgage loans | Substandard
Loans by class categorized by internally assigned risk grades
Total loans	0	0
Multi-family | Mortgage loans | Doubtful
Loans by class categorized by internally assigned risk grades
Total loans	0	0
Residential real estate mortgage loans | Mortgage loans
Loans by class categorized by internally assigned risk grades
Total loans	493,144	519,763
Residential real estate mortgage loans | Mortgage loans | Residential mortgage
Loans by class categorized by internally assigned risk grades
Total loans	424,512	448,515
Residential real estate mortgage loans | Mortgage loans | Residential mortgage | Pass
Loans by class categorized by internally assigned risk grades
Total loans	408,933	438,891
Residential real estate mortgage loans | Mortgage loans | Residential mortgage | Special Mention
Loans by class categorized by internally assigned risk grades
Total loans	11,490	8,510
Residential real estate mortgage loans | Mortgage loans | Residential mortgage | Substandard
Loans by class categorized by internally assigned risk grades
Total loans	4,089	1,114
Residential real estate mortgage loans | Mortgage loans | Residential mortgage | Doubtful
Loans by class categorized by internally assigned risk grades
Total loans	0	0
Residential real estate mortgage loans | Mortgage loans | Home equity
Loans by class categorized by internally assigned risk grades
Total loans	68,632	71,248
Residential real estate mortgage loans | Mortgage loans | Home equity | Pass
Loans by class categorized by internally assigned risk grades
Total loans	67,016	68,480
Residential real estate mortgage loans | Mortgage loans | Home equity | Special Mention
Loans by class categorized by internally assigned risk grades
Total loans	910	1,594
Residential real estate mortgage loans | Mortgage loans | Home equity | Substandard
Loans by class categorized by internally assigned risk grades
Total loans	706	1,174
Residential real estate mortgage loans | Mortgage loans | Home equity | Doubtful
Loans by class categorized by internally assigned risk grades
Total loans	0	0
Commercial, industrial and agricultural loans
Loans by class categorized by internally assigned risk grades
Total loans	679,444	645,724
Commercial, industrial and agricultural loans | Secured
Loans by class categorized by internally assigned risk grades
Total loans	174,219	168,540
Commercial, industrial and agricultural loans | Secured | Pass
Loans by class categorized by internally assigned risk grades
Total loans	162,431	147,474
Commercial, industrial and agricultural loans | Secured | Special Mention
Loans by class categorized by internally assigned risk grades
Total loans	2,074	5,536
Commercial, industrial and agricultural loans | Secured | Substandard
Loans by class categorized by internally assigned risk grades
Total loans	9,714	15,530
Commercial, industrial and agricultural loans | Secured | Doubtful
Loans by class categorized by internally assigned risk grades
Total loans	0	0
Commercial, industrial and agricultural loans | Unsecured
Loans by class categorized by internally assigned risk grades
Total loans	505,225	477,184
Commercial, industrial and agricultural loans | Unsecured | Pass
Loans by class categorized by internally assigned risk grades
Total loans	480,982	458,526
Commercial, industrial and agricultural loans | Unsecured | Special Mention
Loans by class categorized by internally assigned risk grades
Total loans	13,596	12,886
Commercial, industrial and agricultural loans | Unsecured | Substandard
Loans by class categorized by internally assigned risk grades
Total loans	10,647	5,772
Commercial, industrial and agricultural loans | Unsecured | Doubtful
Loans by class categorized by internally assigned risk grades
Total loans	0	0
Real estate construction and land loans
Loans by class categorized by internally assigned risk grades
Total loans	97,311	123,393
Real estate construction and land loans | Pass
Loans by class categorized by internally assigned risk grades
Total loans	95,530	123,089
Real estate construction and land loans | Special Mention
Loans by class categorized by internally assigned risk grades
Total loans	0	0
Real estate construction and land loans | Substandard
Loans by class categorized by internally assigned risk grades
Total loans	1,781	304
Real estate construction and land loans | Doubtful
Loans by class categorized by internally assigned risk grades
Total loans	0	0
Installment/consumer loans
Loans by class categorized by internally assigned risk grades
Total loans	24,836	20,509
Installment/consumer loans | Pass
Loans by class categorized by internally assigned risk grades
Total loans	23,976	20,464
Installment/consumer loans | Special Mention
Loans by class categorized by internally assigned risk grades
Total loans	103	9
Installment/consumer loans | Substandard
Loans by class categorized by internally assigned risk grades
Total loans	757	36
Installment/consumer loans | Doubtful
Loans by class categorized by internally assigned risk grades
Total loans	$ 0	$ 0