CAPITAL STOCK - Activity of Common Stock Outstanding (Details) - Common Stock - shares shares in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Common Stock [Roll Forward]
Balance, beginning of period (in shares)	17,401	17,316	17,197
Issuance of shares for compensation net of withholding (in shares)	59	85	119
Issuance of common stock related to equity distribution agreements (in shares)	0	0	0
Balance, end of period (in shares)	17,460	17,401	17,316