REVENUE FROM CONTRACTS WITH CUSTOMERS Table 1 - Contract Assets and Liabilities (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Contract assets
Noncurrent portion	$ 1,212	$ 1,158	$ 1,003	$ 539
Total	3,430	2,641	3,143	2,605
Additions	2,670	2,674
Transfer to accounts receivable	(2,258)	(2,638)
Transfer to revenues, including amounts reported in discontinued operations, contract assets	(125)	0
Total activity	287	36
Contract liabilities
Noncurrent portion	(45,445)	(39,973)	(40,289)	(38,945)
Total	(65,680)	(63,661)	(61,372)	(85,881)
Additions	(34,156)	(24,537)
Transfer to revenues, including amounts reported in discontinued operations, contract liabilities	29,848	46,757
Total activity	(4,308)	22,220
Other current assets
Contract assets
Current portion/Held for sale	2,218	1,483	2,140	2,066
Accrued liabilities
Contract liabilities
Current portion/Held for sale	$ (20,235)	$ (23,688)	(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)

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

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