STOCKHOLDERS' EQUITY - Common Stock (Details) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Increase (Decrease) in Stockholders' Equity
Shares outstanding, beginning (in shares)	48,706,000	48,498,000	48,102,000
Purchase of common stock (in shares)			(17,000)
Shares issued under stock incentive plan, net of awards surrender to pay applicable taxes (in shares)	171,000	205,000	385,000
Exercise of stock options (in shares)			22,000
Shares issued to Board of Directors in lieu of cash (in shares)	2,000	3,000	6,000
Shares outstanding, ending (in shares)	48,879,000	48,706,000	48,498,000