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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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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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.

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A bank's noninterest bearing demand deposits in other banks (such as correspondents).

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Period of time between issuance and maturity of customer deposits, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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