ALLOWANCE FOR LOAN LOSSES - Changes in the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Allowance for Loan Losses
Beginning balance	$ 31,418	$ 31,707	$ 31,707
Charge-offs	(246)	0
Recoveries	12	305
Provision (Credit)	600	800
Ending balance	31,784	32,812	31,418
Commercial Real Estate \| Mortgage loans
Allowance for Loan Losses
Beginning balance	10,792	11,048	11,048
Charge-offs	0	0
Recoveries	0	0
Provision (Credit)	307	286
Ending balance	11,099	11,334	10,792
Multi-family \| Mortgage loans
Allowance for Loan Losses
Beginning balance	2,566	4,521	4,521
Charge-offs	0	0
Recoveries	0	0
Provision (Credit)	(9)	(1,519)
Ending balance	2,557	3,002	2,566
Residential real estate mortgage loans \| Mortgage loans
Allowance for Loan Losses
Beginning balance	3,935	2,438	2,438
Charge-offs	0	0
Recoveries	1	1
Provision (Credit)	(562)	1,056
Ending balance	3,374	3,495	3,935
Commercial, industrial and agricultural loans
Allowance for Loan Losses
Beginning balance	12,722	12,838	12,838
Charge-offs	(242)	0
Recoveries	11	304
Provision (Credit)	582	913
Ending balance	13,073	14,055	12,722
Real estate construction and land loans
Allowance for Loan Losses
Beginning balance	1,297	740	740
Charge-offs	0	0
Recoveries	0	0
Provision (Credit)	229	81
Ending balance	1,526	821	1,297
Installment/consumer loans
Allowance for Loan Losses
Beginning balance	106	122	122
Charge-offs	(4)	0
Recoveries	0	0
Provision (Credit)	53	(17)
Ending balance	$ 155	$ 105	$ 106

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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