v3.21.2

Summary of significant accounting policies (Contract Liabilities) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Summary of significant accounting policies |  |  |
Unbilled loans mature amounted | $ 0 | $ 0 |
Balance | 8,000 | 6,000 |
Acquisition of Suns Tower Limited |  |  | $ 10,000
Revenue recognized from beginning contract liability balance | (8,000) | (6,000) | (10,000)
Advances received from customers related to unsatisfied performance obligations | 3,000 | 8,000 | 6,000
Balance | $ 3,000 | $ 8,000 | $ 6,000

X
- Definition liability due to acquisition. + References No definition available. + Details
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Period Type: | duration

X
- Definition Advance From Customers Related to Unsatisfied performance Obligation. + References No definition available. + Details
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- Definition It represents unbilled loans amount. + References No definition available. + Details
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Balance Type: | debit
Period Type: | instant

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- References No definition available. + Details
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X
- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable. + References Reference 1: 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 2: 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 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130532-203044 + Details
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- Definition Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due. + 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 (b) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130549-203045 + Details
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