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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