WEIGHTED AVERAGE SHARE COUNTS (DILUTED SHARES TABLE) (Details) - shares shares in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]
Shares used in basic earnings per share calculation	46,736	46,732	46,619	46,498	46,487	46,481	46,318	46,203	46,647	46,373	46,064
Effect of dilutive securities:
Stock options											6
Restricted stock units									318	349	314
Performance-based restricted stock units									28	36	1
Total effects of dilutive securities									346	385	321
Shares used in dilutive earnings per share calculation	47,232	47,031	46,861	46,813	46,830	46,768	46,684	46,590	46,993	46,758	46,385