NET INCOME PER SHARE (Details) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share [Abstract]
Weighted-average number of basic common shares outstanding	40,974,000	43,082,000	47,446,000
Weighted-average dilutive stock options, restricted stock units and performance share units	158,000	203,000	236,000
Assumed conversion of convertible senior notes	28,000	224,000	335,000
Weighted-average number of diluted common and common equivalent shares outstanding	41,160,000	43,509,000	48,017,000
Antidilutive securities excluded from computation of earnings per share, amount	125,000