v3.21.2

REVENUE FROM CONTRACTS WITH CUSTOMERS Table 1 - Contract Assets and Liabilities (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019
Contract assets
Noncurrent portion	$ 585	$ 1,035	$ 932	$ 1,003
Total	1,268	3,205	3,626	3,143
Additions	1,924	4,020
Transfer to accounts receivable	(3,907)	(3,708)
Transfer to revenues, contract assets	(375)	(250)
Total activity	(2,358)	62
Contract liabilities
Noncurrent portion	(46,056)	(46,189)	(47,537)	(40,289)
Total	(62,271)	(67,304)	(69,556)	(61,372)
Additions	(29,874)	(54,120)
Transfer to revenues, contract liabilities	37,159	48,188
Total activity	7,285	(5,932)
Assets Held for Sale
Contract assets
Current portion	197	0
Liabilities Held for Sale
Contract liabilities
Current portion	(1,021)	0
Other current assets
Contract assets
Current portion	486	2,170	2,694	2,140
Accrued liabilities
Contract liabilities
Current portion	$ (15,194)	$ (21,115)	$ (22,019)	$ (21,083)

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