ACCOUNTING POLICIES - Stock-Based Compensation (Details)	12 Months Ended
	Dec. 31, 2018
Long-term stock awards | Minimum
Stock-based compensation
Award vesting period	5 years
Long-term stock awards | Maximum
Stock-based compensation
Award vesting period	10 years
Phantom Share Units (PSUs) | Minimum
Stock-based compensation
Award vesting period	5 years
Phantom Share Units (PSUs) | Maximum
Stock-based compensation
Award vesting period	10 years
Stock Appreciation Rights (SARs)
Stock-based compensation
Award vesting period	5 years
Age 65 Or Older | Long-term stock awards
Stock-based compensation
Award vesting period	5 years