v3.21.1

Contract assets and contract liabilities (Tables) | 3 Months Ended
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Mar. 31, 2021
Contract assets and contract liabilities |
Schedule of contract asset, net and contract liability, net balance from customers | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Contract | ​ | Contract
​ |  | Assets, Net |  | Liabilities, Net
Balance at December 31, 2020 | ​ | $ | 547 | ​ | $ | 224,754
Balance at March 31, 2021 (1) | ​ |  | 473 | ​ | ​ | 236,465
Change | ​ | $ | (74) | ​ | $ | 11,711
Schedule of remaining performance obligations included in revenue | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three Months Ended
​ | ​ | March 31,
​ | ​ | 2021 | ​ | 2020
Amounts included in the beginning of period contract liability balance | ​ | $ | 28,348 | ​ | $ | 24,970
Amounts associated with performance obligations satisfied in previous periods | ​ | ​ | — | ​ | ​ | 13

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- Definition Tabular disclosure of receivable, contract asset, and contract liability from contract with customer. Includes, but is not limited to, change in contract asset and contract liability. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130551-203045 + Details
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- Definition Tabular disclosure of expected timing for satisfying remaining performance obligation. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045 + Details
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