RETIREMENT PLANS (Narrative) (Details)	12 Months Ended
Dec. 31, 2019 USD ($) person	Dec. 31, 2018 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Accumulated benefit obligation	$ 33,080,000	$ 29,115,000
Corporation common stock included in equity securities, percentage of total plan assets	6.00%	7.00%
Percentage of participants average monthly pay used to calculate benefit accruals	0.75%
Maximum years of benefit used to calculate benefit accruals	25 years
Number of active, vested terminated, and retired persons in the Plan \| person	348
Employee contribution percentage, maximum	100.00%
Additional compensation contributed to plan	50.00%
Balance accrued included in other liabilities	$ 3,196,000	$ 2,932,000
Annual expense included in salaries and benefits expense	$ 493,000	463,000
Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage over employees' gross pay	3.00%
Maximum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage over employees' gross pay	5.00%
Banking Subsidiary
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer Match Percentage of Income	3.00%
Employer Contributions to and Expenses for the Plan	$ 709,000	664,000
Insurance Subsidiary
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer Contributions to and Expenses for the Plan	$ 123,000	97,000
Non-highly compensated employees \| Insurance Subsidiary
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer Match Percentage of Income	6.00%
Highly compensated employees \| Insurance Subsidiary
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer Match Percentage of Income	3.00%
Corporation common stock
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Fair value of plan assets	$ 2,854,000	$ 2,882,000

Corporation Common Stock Included in Equity Securities, Percentage of Total Plan Assets

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Amount of employer security in which defined benefit plan asset is invested. Includes, but is not limited to, security issued or managed by related party of employer.

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Amount of cost of providing special or contractual termination benefits payable from defined benefit plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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