EMPLOYEE BENEFITS AND STOCK BASED COMPENSATION (Narrative) (Details) - USD ($)	12 Months Ended			58 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Apr. 20, 2015
Defined Benefit Plan Disclosure [Line Items]
Deferred compensation plans obligation to Board of Directors	$ 11,100,000	$ 10,400,000		$ 10,400,000
Maximum term of stock options	10 years
Stock options granted	0	0		0
Stock options term from the grant date	1 year 7 months 24 days
Number of stock option awards exercised	63,476	88,409	60,637
Intrinsic value of stock options exercised	$ 1,200,000	$ 1,171,000	$ 544,000
Fair value of stock options exercised	2,200,000	2,594,000	1,400,000
Cash received from the exercise of stock options	1,000,000	1,423,000	886,000
Tax benefit from exercise of equity-based awards	370,000	381,000	178,000
Fair value of stock options vested	$ 47,000	159,000	316,000
Restricted stock vesting percentage	50.00%
Intrinsic value of stock options outstanding	$ 2,708,076	$ 3,900,000	$ 2,800,000	$ 3,900,000
Unamortized compensation costs	$ 9,089,000
Minimum
Defined Benefit Plan Disclosure [Line Items]
Hours of service required for eligibility under plan	1000 hours
1% through 3%
Defined Benefit Plan Disclosure [Line Items]
Percentage of employer's match for 401(k) plan	100.00%
1% through 3% | Minimum
Defined Benefit Plan Disclosure [Line Items]
Percentage of employee's gross pay for 401(k) plan	1.00%
1% through 3% | Maximum
Defined Benefit Plan Disclosure [Line Items]
Percentage of employee's gross pay for 401(k) plan	3.00%
4% through 5%
Defined Benefit Plan Disclosure [Line Items]
Percentage of employer's match for 401(k) plan	50.00%
4% through 5% | Minimum
Defined Benefit Plan Disclosure [Line Items]
Percentage of employee's gross pay for 401(k) plan	4.00%
4% through 5% | Maximum
Defined Benefit Plan Disclosure [Line Items]
Percentage of employee's gross pay for 401(k) plan	5.00%
Stock and Incentive Plan
Defined Benefit Plan Disclosure [Line Items]
Number of shares authorized to be issued, maximum	2,500,000
Number of shares available for future issuance	1,560,728
2011 Plan
Defined Benefit Plan Disclosure [Line Items]
Number of shares authorized to be issued, maximum					1,000,000
Restricted Stock | Minimum
Defined Benefit Plan Disclosure [Line Items]
Vesting period of restricted stock awards and performance stock units	3 years
Restricted Stock | Maximum
Defined Benefit Plan Disclosure [Line Items]
Vesting period of restricted stock awards and performance stock units	4 years