Subsequent Events	12 Months Ended
Dec. 31, 2024
Subsequent Events [Abstract]
Subsequent Events	16. Subsequent Events On January 9, 2025, the board of directors (the “Board”) of AlloVir, Inc. determined to effect a 1-for-23 reverse stock split of AlloVir’s common stock, par value $0.0001 per share. Refer to Note 1 for additional information. Pursuant to the Merger Agreement, Kalaris is permitted to enter into the Additional Permitted Bridge Financing. On January 10, 2025, as a part of the Additional Permitted Bridge Financing, Kalaris issued a convertible promissory note in an aggregate principal amount of up to $7.5 million to AlloVir, under which AlloVir funded a principal amount of $3.75 million, and Kalaris issued convertible promissory notes in an aggregate principal amount of $3.75 million to existing Kalaris stockholders. Upon the closing of the Merger, the AlloVir note will be cancelled and the aggregate amount outstanding under the AlloVir note will be added to AlloVir’s net cash.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org/855/tableOfContent

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

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