EXIT ACTIVITIES AND RESTRUCTURING - Schedule of Exit Activities and Restructuring Charges (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Reserve [Roll Forward]
Balance	$ 2,601	$ 4,816	$ 4,703
Initial Charges	1,629	3,484	3,359
Plan Adjustments	207	1,687	2,932
Cash Payments	(4,237)	(7,386)	(6,178)
Balance	200	2,601	4,816
Activity of 2019 Restructuring | Real estate obligations
Restructuring Reserve [Roll Forward]
Balance	0
Initial Charges	1,629
Plan Adjustments	(116)
Cash Payments	(1,377)
Balance	136	0
Activity of 2018 Restructuring | Real estate obligations
Restructuring Reserve [Roll Forward]
Balance	1,922	0
Initial Charges	0	3,484
Plan Adjustments	187	1,023
Cash Payments	(2,109)	(2,585)
Balance	0	1,922	0
Activity of 2017 Restructuring | Real estate obligations
Restructuring Reserve [Roll Forward]
Balance	100	3,380	0
Initial Charges	0	0	3,359
Plan Adjustments	1	316	1,741
Cash Payments	(101)	(3,596)	(1,720)
Balance	0	100	3,380
Activity of 2016 Restructuring | Real estate obligations
Restructuring Reserve [Roll Forward]
Balance	125	247	933
Initial Charges	0	0	0
Plan Adjustments	11	39	82
Cash Payments	(136)	(161)	(768)
Balance	0	125	247
Activity of 2016 Restructuring | Severance
Restructuring Reserve [Roll Forward]
Balance	0	46	1,911
Initial Charges		0	0
Plan Adjustments		34	957
Cash Payments		(80)	(2,822)
Balance		0	46
Activity of 2015 Restructuring | Real estate obligations
Restructuring Reserve [Roll Forward]
Balance	27	64	111
Initial Charges	0	0	0
Plan Adjustments	29	4	0
Cash Payments	(56)	(41)	(47)
Balance	0	27	64
Activity of 2015 Restructuring | Service contracts
Restructuring Reserve [Roll Forward]
Balance	221	388	565
Initial Charges	0	0	0
Plan Adjustments	41	31	21
Cash Payments	(198)	(198)	(198)
Balance	64	221	388
Activity of 2014 Restructuring | Real estate obligations
Restructuring Reserve [Roll Forward]
Balance	206	691	1,183
Initial Charges	0	0	0
Plan Adjustments	54	240	131
Cash Payments	(260)	(725)	(623)
Balance	$ 0	$ 206	$ 691