FAIR VALUE - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended	9 Months Ended
		Sep. 30, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	[1]		$ 400
Capitalization Rates Utilized To Determine Fair Value Of Underlying Collateral Averaged Percentage		7.70%	7.70%
Loans and Leases Receivable, Allowance		$ 26,232	$ 26,232	$ 26,000	$ 23,400	$ 22,684	$ 20,725	$ 19,128
Loans Receivable [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3			800
Other Real Estate Owned And Other Reductions		600	600
Other Real Estate Owned [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Other Real Estate Revenue			4,200
Loans Receivable, Fair Value Disclosure		4,200	4,200		4,100
Loans and Leases Receivable, Allowance		1,400	1,400		$ 400
Other Real Estate, Disposals			4,400
Other Real Estate, Improvements		$ 6,000	$ 1,200

[1] See Note D for further detail of fair value of individual investment categories.