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v3.21.2

Contract balances (Details 2) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020 | Dec. 31, 2020
Revenue from Contract with Customer [Abstract] |  |  |  |  |
Contract assets | $ 147,033 |  | $ 147,033 |  | $ 104,345
Change in contract assets |  |  | 42,688 |  |
Contract liabilities - current | (146,116) |  | (146,116) |  | (158,603)
Change in contract liabilities - current |  |  | 12,487 |  |
Contract liabilities - noncurrent | (160) |  | (160) |  | (52)
Change in contract liabilities - noncurrent |  |  | (108) |  |
Net contract assets (liabilities) | 757 |  | 757 |  | $ (54,310)
Change in net contract liabilities |  |  | 55,067 |  |
Amounts included in contract liability at the beginning of the period | 21,900 | $ 32,300 | 145,300 | $ 121,700 |
Amounts from performance obligations satisfied in prior periods | $ 27,300 | $ 31,900 | $ 54,600 | $ 42,900 |

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- Definition Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130549-203045 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130531-203044 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130533-203044 + Details
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