CAPITAL STOCK AND SHARE-BASED COMPENSATION - Stock Option Valuation Assumptions (Details) - Stock Option [Member] - $ / shares |
12 Months Ended | ||
---|---|---|---|
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
|
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
Risk Free Rate, minimum | 1.44% | 2.56% | 1.99% |
Risk Free Rate, maximum | 2.53% | 3.04% | 2.16% |
Expected Volatility, minimum | 42.46% | 42.00% | 50.18% |
Expected Volatility, maximum | 43.83% | 45.32% | 51.81% |
Weighted Average Fair Value | $ 54.42 | $ 42.48 | $ 28.02 |
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate | 0.00% | 0.00% | 0.00% |
Minimum [Member] | |||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
Expected Term | 6 years | 4 years 1 month 13 days | 5 years 9 months 11 days |
Maximum [Member] | |||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
Expected Term | 6 years 3 months | 6 years 3 months | 6 years 3 months |