Balance Sheet Components - Other Prepaid Expenses and Current Assets (Details) - USD ($) $ in Thousands |
Jun. 30, 2026 |
Dec. 31, 2025 |
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| Balance Sheet Components [Line Item] | ||
| Prepaid subscriptions | $ 2,394 | $ 2,088 |
| Interest receivable | 2,088 | 1,343 |
| Tax receivable | 1,048 | 740 |
| Stock options exercise proceeds receivable | 724 | |
| Prepaid insurance | 158 | 744 |
| Prepaid credit voucher for clinical manufacturing | 13 | 683 |
| Other | 978 | 1,142 |
| Total other prepaid expenses and current assets | 7,403 | $ 6,740 |
| Location, Statement of Financial Position, Balance [Axis]: us-gaap:OtherAssetsNoncurrent | ||
| Balance Sheet Components [Line Item] | ||
| Prepaid credit voucher for clinical manufacturing included in other assets, non-current | 900 | |
| Location, Statement of Financial Position, Balance [Axis]: alms:OtherPrepaidExpenseAndAssetsCurrent | ||
| Balance Sheet Components [Line Item] | ||
| Prepaid credit voucher for clinical manufacturing included in other assets, non-current | $ 13 |
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- References No definition available.
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- Definition Amount of prepaid credit voucher for clinical manufacturing that provide economic benefits within a future period of one year or the normal operating cycle, if longer. No definition available.
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- Definition Amount of prepaid credit voucher for clinical manufacturing that provide economic benefits within a future period beyond the one year or the normal operating cycle, if longer. No definition available.
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- Definition Amount of asset related to consideration paid in advance for subscription that provides economic benefits within a future period of one year or the normal operating cycle, if longer. No definition available.
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- Definition Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from stock options exercise proceeds receivable. No definition available.
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- Definition Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Carrying amount as of the balance sheet date of current interest earned but not received. Also called accrued interest or accrued interest receivable. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of asset related to consideration paid in advance for other costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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