REVENUE FROM CONTRACTS WITH CUSTOMERS Table 1 - Contract Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Contract assets
Noncurrent portion	$ 1,399	$ 893	$ 1,003	$ 539
Total	3,211	2,274	3,143	2,605
Additions	1,357	941
Transfer to accounts receivable	(1,289)	(1,272)
Total activity	68	(331)
Contract liabilities
Noncurrent portion	(42,069)	(40,463)	(40,289)	(38,945)
Total	(62,490)	(62,261)	(61,372)	(85,881)
Additions	(11,883)	(11,094)
Transfer to revenues, including amounts reported in discontinued operations	10,765	34,714
Total activity	(1,118)	23,620
Other current assets
Contract assets
Current portion/Held for sale	1,812	1,381	2,140	2,066
Accrued liabilities
Contract liabilities
Current portion/Held for sale	$ (20,421)	$ (21,798)	(21,083)	(21,579)
Assets held for sale
Contract assets
Current portion/Held for sale			0	0
Liabilities held for sale
Contract liabilities
Current portion/Held for sale			$ 0	$ (25,357)

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