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

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