LOANS AND ALLOWANCE FOR CREDIT LOSSES Summary of Nonaccrual Loans and Loans Past Due (Details) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Jan. 01, 2020	Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans	$ 47,390	$ 44,884	$ 39,640	$ 39,640
Nonaccrual With No Related Allowance	20,474
Past Due 90 Days or Greater and Accruing	12,876
Interest Income Recognized on Nonaccrual	0
Commercial | Construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans	2,034	0	0
Nonaccrual With No Related Allowance	2,034
Past Due 90 Days or Greater and Accruing	0
Interest Income Recognized on Nonaccrual	0
Commercial | Commercial multifamily
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans	884	753	811
Nonaccrual With No Related Allowance	598
Past Due 90 Days or Greater and Accruing	163
Interest Income Recognized on Nonaccrual	0
Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				20,119
Commercial real estate | Construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				0
Commercial real estate | Commercial real estate owner occupied
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans	8,291	6,513	15,389
Nonaccrual With No Related Allowance	2,429
Past Due 90 Days or Greater and Accruing	179
Interest Income Recognized on Nonaccrual	0
Commercial real estate | Commercial real estate non-owner occupied
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans	3,074	2,372	1,031
Nonaccrual With No Related Allowance	2,170
Past Due 90 Days or Greater and Accruing	7,338
Interest Income Recognized on Nonaccrual	0
Commercial real estate | Other commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				20,119
Commercial and industrial loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans	10,300	8,103	5,465	11,373
Nonaccrual With No Related Allowance	3,869
Past Due 90 Days or Greater and Accruing	3,443
Interest Income Recognized on Nonaccrual	0
Financing receivable, nonaccrual, medallion loans, fair value	2,800
Financing receivable, nonaccrual, medallion loans, contractual balance	66,400
Commercial and industrial loans | Commercial and industrial - other
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans	3,969	6,173	5,753
Nonaccrual With No Related Allowance	2,959
Past Due 90 Days or Greater and Accruing	0
Interest Income Recognized on Nonaccrual	0
Residential mortgages
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				3,343
Residential mortgages | Construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				0
Residential mortgages | Residential real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans	9,555	13,997	6,411
Nonaccrual With No Related Allowance	5,876
Past Due 90 Days or Greater and Accruing	1,310
Interest Income Recognized on Nonaccrual	0
Residential mortgages | 1 to 4 Family
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				3,343
Consumer loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				4,805
Consumer loans | Home equity
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans	3,628	2,405	1,798	1,812
Nonaccrual With No Related Allowance	490
Past Due 90 Days or Greater and Accruing	394
Interest Income Recognized on Nonaccrual	0
Consumer loans | Consumer other
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans	5,655	$ 4,568	$ 2,982
Nonaccrual With No Related Allowance	49
Past Due 90 Days or Greater and Accruing	49
Interest Income Recognized on Nonaccrual	$ 0
Consumer loans | Auto And Other Receivable
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				2,993
Business Activities Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				32,536
Past Due 90 Days or Greater and Accruing				975
Business Activities Loans | Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				15,623
Past Due 90 Days or Greater and Accruing				0
Business Activities Loans | Commercial real estate | Construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				0
Past Due 90 Days or Greater and Accruing				0
Business Activities Loans | Commercial real estate | Other commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				15,623
Past Due 90 Days or Greater and Accruing				0
Business Activities Loans | Commercial and industrial loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				10,540
Past Due 90 Days or Greater and Accruing				122
Business Activities Loans | Residential mortgages
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				2,550
Past Due 90 Days or Greater and Accruing				800
Business Activities Loans | Residential mortgages | Construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				0
Past Due 90 Days or Greater and Accruing				0
Business Activities Loans | Residential mortgages | 1 to 4 Family
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				2,550
Past Due 90 Days or Greater and Accruing				800
Business Activities Loans | Consumer loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				3,823
Past Due 90 Days or Greater and Accruing				53
Business Activities Loans | Consumer loans | Home equity
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				1,095
Past Due 90 Days or Greater and Accruing				52
Business Activities Loans | Consumer loans | Auto And Other Receivable
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				2,728
Past Due 90 Days or Greater and Accruing				1
Acquired Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				7,104
Past Due 90 Days or Greater and Accruing				6,404
Acquired Loans | Commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				4,496
Past Due 90 Days or Greater and Accruing				5,751
Acquired Loans | Commercial real estate | Construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				0
Past Due 90 Days or Greater and Accruing				0
Acquired Loans | Commercial real estate | Other commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				4,496
Past Due 90 Days or Greater and Accruing				5,751
Acquired Loans | Commercial and industrial loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				833
Past Due 90 Days or Greater and Accruing				442
Acquired Loans | Residential mortgages
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				793
Past Due 90 Days or Greater and Accruing				139
Acquired Loans | Residential mortgages | Construction
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				0
Past Due 90 Days or Greater and Accruing				0
Acquired Loans | Residential mortgages | 1 to 4 Family
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				793
Past Due 90 Days or Greater and Accruing				139
Acquired Loans | Consumer loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				982
Past Due 90 Days or Greater and Accruing				72
Acquired Loans | Consumer loans | Home equity
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				717
Past Due 90 Days or Greater and Accruing				72
Acquired Loans | Consumer loans | Auto And Other Receivable
Financing Receivable, Allowance for Credit Loss [Line Items]
Non-accrual loans				265
Past Due 90 Days or Greater and Accruing				$ 0