CAPITAL STOCK AND STOCK AWARD PLANS - Summary of Employee Stock Purchase Plan Activity (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Purchased By Employees (in shares)	191,823	215,613	225,241
Aggregate Cost to Employees	$ 14,682	$ 14,048	$ 14,032
Expense Recognized By the Company	87,791	41,805	37,565
Company expense on ESPP discount
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expense Recognized By the Company	$ 2,591	$ 2,479	$ 2,475

Number of shares issued during the period as a result of an employee stock purchase plan.

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Period Type:	duration