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Contract balances (Details 2) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Revenue from Contract with Customer [Abstract] |  |  |
Contract assets | $ 104,345 | $ 109,078 | $ 104,239
Change in contract assets | (4,733) | 4,839 |
Contract liabilities - current | (158,603) | (142,768) | (93,901)
Change in contract liabilities - current | (15,835) | (48,867) |
Contract liabilities - noncurrent | (52) | (19) | (135)
Change in contract liabilities - noncurrent | (33) | 116 |
Net contract assets (liabilities) | (54,310) | (33,709) | $ 10,203
Change in net contract assets (liabilities) | (20,601) | (43,912) |
Amounts included in contract liability at the beginning of the period | 138,200 | 89,000 |
Amounts from performance obligations satisfied in prior periods | $ 58,800 | $ 44,100 |

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- Definition Total of net contract assets and liabilities + References No definition available. + Details
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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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