REVENUE FROM CONTRACTS WITH CUSTOMERS Table 1 - Contract Assets and Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Contract assets
Noncurrent portion	$ 932	$ 1,003	$ 539	$ 171
Total	3,626	3,143	2,605	2,127
Additions	5,686	4,890	3,281
Transfer to accounts receivable	(4,828)	(4,352)	(2,803)
Transfer to revenues, including amounts reported in discontinued operations, contract assets	(375)	0	0
Total activity	483	538	478
Contract liabilities
Current portion/Held for sale	(22,019)	(21,083)
Noncurrent portion	(47,537)	(40,289)	(38,945)	(46,361)
Total	(69,556)	(61,372)	(85,881)	(60,464)
Additions	(69,830)	(52,957)	(83,243)
Transfer to revenues, including amounts reported in discontinued operations, contract liabilities	61,646	77,466	57,826
Total activity	(8,184)	24,509	(25,417)
Other current assets
Contract assets
Current portion/Held for sale	2,694	2,140	2,066	1,956
Accrued liabilities
Contract liabilities
Current portion/Held for sale	(22,019)	(21,083)	(21,579)	(13,801)
Assets Held for Sale [Member]
Contract assets
Current portion/Held for sale	0	0	0	0
Liabilities held for sale [Member]
Contract liabilities
Current portion/Held for sale	$ 0	$ 0	$ (25,357)	$ (302)

Total change in contract with customer asset balance in the current period.

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