EARNINGS PER SHARE - Additional Items Excluded or Included in Diluted Earnings Calculations (Details) - shares	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Stock options
Earnings per share [line items]
Stock options that were anti-dilutive and not included in diluted earnings per share calculations (in shares)	0	0	0
PSUs
Earnings per share [line items]
The effect of PSUs included in diluted earnings per share calculations (in shares)	885,879	892,077	498,040

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes of the table.

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