ALLOWANCE FOR LOAN LOSSES AND CREDIT QUALITY - Loans By Class Modified As Troubled Debt Restructuring (Details) $ in Thousands	3 Months Ended		6 Months Ended		9 Months Ended
	Jun. 30, 2020 USD ($) loan	Sep. 30, 2019	Jun. 30, 2020 USD ($) loan	Jun. 30, 2019 USD ($) loan	Sep. 30, 2019
Financing Receivable, Modifications
Pre-Modification Outstanding Recorded Investment			$ 6,066	$ 35
Post-Modification Outstanding Recorded Investment			$ 5,533	$ 35
Extension period for modified repayment terms	0 months		0 months	0 months
Modified Repayment Terms
Financing Receivable, Modifications
Number of Loans \| loan	3		4	1
Modified Repayment Terms \| Minimum
Financing Receivable, Modifications
Extension period for modified repayment terms		0 months			0 months
All Modifications [Member]
Financing Receivable, Modifications
Number of Loans \| loan	3		4	1
Commercial and Industrial Loans [Member]
Financing Receivable, Modifications
Pre-Modification Outstanding Recorded Investment	$ 5,278
Post-Modification Outstanding Recorded Investment	5,411
Commercial and Industrial Loans [Member] \| Working Capital Lines of Credit Loans [Member]
Financing Receivable, Modifications
Pre-Modification Outstanding Recorded Investment	250		$ 250	$ 35
Post-Modification Outstanding Recorded Investment	$ 315		$ 315	$ 35
Extension period for modified repayment terms	0 months		0 months	0 months
Commercial and Industrial Loans [Member] \| Working Capital Lines of Credit Loans [Member] \| Modified Repayment Terms
Financing Receivable, Modifications
Number of Loans \| loan	1		1	1
Commercial and Industrial Loans [Member] \| Working Capital Lines of Credit Loans [Member] \| All Modifications [Member]
Financing Receivable, Modifications
Number of Loans \| loan	1		1	1
Commercial and Industrial Loans [Member] \| Non-working Capital Loans [Member]
Financing Receivable, Modifications
Pre-Modification Outstanding Recorded Investment	$ 3,500		$ 4,288
Post-Modification Outstanding Recorded Investment	$ 3,569		$ 3,691
Extension period for modified repayment terms	0 months		0 months
Commercial and Industrial Loans [Member] \| Non-working Capital Loans [Member] \| Modified Repayment Terms
Financing Receivable, Modifications
Number of Loans \| loan	1		2
Commercial and Industrial Loans [Member] \| Non-working Capital Loans [Member] \| Modified Repayment Terms \| Minimum
Financing Receivable, Modifications
Extension period for modified repayment terms		0 months
Commercial and Industrial Loans [Member] \| Non-working Capital Loans [Member] \| All Modifications [Member]
Financing Receivable, Modifications
Number of Loans \| loan	1		2
Commercial Real Estate and Multi-family Residential Loans [Member] \| Non-working Capital Loans [Member] \| Modified Repayment Terms
Financing Receivable, Modifications
Number of Loans \| loan	1
Commercial Real Estate and Multi-family Residential Loans [Member] \| Owner Occupied Loans [Member]
Financing Receivable, Modifications
Pre-Modification Outstanding Recorded Investment	$ 1,528		$ 1,528
Post-Modification Outstanding Recorded Investment	$ 1,527		$ 1,527
Extension period for modified repayment terms	0 months		0 months
Commercial Real Estate and Multi-family Residential Loans [Member] \| Owner Occupied Loans [Member] \| Modified Repayment Terms
Financing Receivable, Modifications
Number of Loans \| loan			1
Commercial Real Estate and Multi-family Residential Loans [Member] \| Owner Occupied Loans [Member] \| All Modifications [Member]
Financing Receivable, Modifications
Number of Loans \| loan			1