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Stock Incentive Plans (Details 6)
1 Months Ended 12 Months Ended
Jan. 31, 2018
Mar. 31, 2017
Dec. 31, 2018
Daily expected stock price volatility     47.00%
Daily expected dividend yield     0.00%
Average daily risk free interest rate     2.95%
Restricted Stock Units (RSUs) [Member]      
Daily expected stock price volatility 4.2806% 4.4237%  
Daily expected mean return on equity (0.2575%) (0.2226%)  
Daily expected dividend yield 0.00% 0.00%  
Average daily risk free interest rate 0.0078% 0.0063%