Significant accounting policies - Concentration of Credit Risk (Details)	3 Months Ended	9 Months Ended
Sep. 30, 2021 customer	Sep. 30, 2021 Institution customer
Concentrations of credit risk and off-balance sheet risk
Off-balance sheet concentrations of credit risk description		As of September 30, 2021 the Company’s cash, cash equivalents and investments were deposited at three financial institutions and it has no significant off-balance sheet concentrations of credit risk, such as foreign currency exchange contracts, option contracts or other hedging arrangements.
Number of financial institutions in which cash, cash equivalents and investments were deposited \| Institution		3
Trade accounts receivable \| Credit Concentration Risk \| Secura
Concentrations of credit risk and off-balance sheet risk
Number of customer		1
Trade accounts receivable \| Credit Concentration Risk \| Secura \| Minimum
Concentrations of credit risk and off-balance sheet risk
Percentage		60.00%
Revenue \| Customer Concentration Risk \| Secura
Concentrations of credit risk and off-balance sheet risk
Number of customer	1	1

Description of financial instruments, excluding certain derivatives, with off-balance sheet credit risk (for example, standby letters of credit or financial guarantees), including (1) information about the (shared) activity, region or economic characteristic that identifies the concentration, (2) the face or contract amount of the instrument, (3) the nature and terms of the instrument, including the market risk, cash requirements and accounting policies for it, (4) the maximum amount of loss due to credit risk that would be incurred if the counterparties failed completely to perform according to the terms of the contracts, and any security or collateral that proved to be of no value, (5) the entity's policy of requiring collateral or other security to support financial instruments subject to credit risk, information about access to collateral or other security, and a brief description of the security supporting those financial instruments, and (6) the policy of entering into and a brief description of master netting arrangements to mitigate the credit risk, and the extent to which such arrangements would reduce the maximum amount of loss due to credit risk.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 825
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=108315417&loc=d3e61044-112788

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13537-108611

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration