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EMPLOYEE STOCK COMPENSATION - Weighted Average Fair Value Assumptions (Details) - Stock option awards
12 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Dividend yield 0.00% 3.57% 4.14%
Expected volatility 0.00% 43.30% 43.04%
Expected term 0 years 6 years 6 months 6 years 5 months 12 days
Risk-free interest rate 0.00% 1.61% 1.68%