Summary of significant accounting policies - Narrative (Details)	12 Months Ended
Dec. 31, 2023 USD ($) segment	Dec. 31, 2022 USD ($)
Summary of significant accounting policies
Number of operating segments \| segment	1
Restricted cash	$ 100,000	$ 100,000
Impairment losses	0	0
Deferred offering costs	$ 0	$ 300,000
Expected dividend yield	0.00%

No definition available.

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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

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Amount of cash restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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