Cabaletta Bio, Inc. Quarterly report [Sections 13 or 15(d)]

Quarterly report [Sections 13 or 15(d)]

Fair Value Measurements - Schedule of Debt Securities Classified as Available-for-Sale Investments (Details)

Fair Value Measurements - Schedule of Debt Securities Classified as Available-for-Sale Investments (Details) $ in Thousands	Sep. 30, 2025 USD ($)
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 159,908
Gross Unrealized Gains	26
Gross Unrealized Losses	(3)
Fair value	159,931
Cash
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	2,108
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair value	2,108
Money Market Funds Included in Cash and Cash Equivalents
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	60,206
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair value	60,206
Government securities - due in one year or less
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	99,702
Gross Unrealized Gains	26
Gross Unrealized Losses	(3)
Fair value	99,725
Money Market Funds
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	58,098
Gross Unrealized Gains	0
Gross Unrealized Losses	0
Fair value	$ 58,098

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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+ Details

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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