v3.21.2

Quantitative and qualitative disclosure about market risk - Additional Information (Details) $ in Thousands |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
May 16, 2021 | Dec. 31, 2020 HKD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 | Jun. 30, 2021 HKD ($) | Jun. 30, 2021 USD ($) | Dec. 31, 2019 HKD ($)
Concentration Risk [Line Items] |  |  |  |  |  |  |  |
Provision for loan losses during the period |  |  | $ 1,980 | $ 194 |  |  |  |
Outstanding principal |  | $ 201,647,726 |  |  |  |  |  |
Accrued interest on loans |  | 18,506,257 |  |  |  |  |  |
Cash and bank deposits |  | $ 500,000 |  |  |  | $ 10,340,000 | $ 80,670 | $ 500,000
Maturiy term of time deposits |  |  | 5 years |  |  |  |  |
Alpen Baruch Bank |  |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |  |
Cash at bank |  |  |  |  |  | $ 1,050,000 | $ 8,170 |
Sales Revenue [Member] | Customer concentration |  |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |  |
Concentration risk threshold percentage |  |  |  | 10.00% | 10.00% |  |  |
Sales Revenue [Member] | Customer concentration | Major Customer One [Member] |  |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |  |
Concentration risk percentage |  |  |  | 21.00% | 14.00% |  |  |
Sales Revenue [Member] | Customer concentration | Major Customer Two [Member] |  |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |  |
Concentration risk percentage |  |  |  |  | 23.00% |  |  |
Accounts Receivable [Member] | Customer concentration |  |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |  |
Concentration risk threshold percentage |  |  | 10.00% | 10.00% |  |  |  |
Accounts Receivable [Member] | Customer One [Member] | Customer concentration |  |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |  |
Concentration risk percentage |  |  | 16.00% | 52.00% |  |  |  |
Accounts Receivable [Member] | Customer Two [Member] | Customer concentration |  |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |  |
Concentration risk percentage |  |  | 15.00% |  |  |  |  |
Accounts Receivable [Member] | Customer Three [Member] | Customer concentration |  |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |  |
Concentration risk percentage |  |  | 39.90% |  |  |  |  |
Stockholders' Equity, Total [Member] | Customer concentration |  |  |  |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |  |  |  |
Concentration risk threshold percentage | 2.30% | 2.30% | 2.30% |  |  |  |  |

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- Definition For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 42 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9054-108599 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13531-108611 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 21 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13537-108611 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -SubTopic 10 -Section 50 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592 + Details
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