Nature of business and summary of significant accounting policies - Share repurchases (Details) - USD ($) |
12 Months Ended | |
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Dec. 31, 2021 |
Aug. 31, 2021 |
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| Organization, Consolidation and Presentation of Financial Statements [Abstract] | ||
| Share repurchase program, authorized amount | $ 2,000,000 | |
| Share repurchases (in shares) | 439,725 | |
| Share repurchases | $ 1,601,000 |
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- References No definition available.
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- Definition Amount of stock repurchase plan authorized. No definition available.
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- Definition Number of shares that have been repurchased and retired during the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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