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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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The cash inflow from parent as a source of financing that is recorded as additional paid in capital.

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The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Overview and Basis of Presentation (Details) - USD ($) $ in Thousands	1 Months Ended
	May 31, 2021	Oct. 31, 2013	Mar. 31, 2021	Dec. 31, 2020
Overview And Basis Of Presentation [Line Items]
Retained Earnings (Accumulated Deficit)			$ (69,834)	$ (68,960)
Cash			$ 466
Harvard Bioscience Plan [Member]
Overview And Basis Of Presentation [Line Items]
Proceeds from Contributions from Parent		$ 15,000
Subsequent Event [Member] \| Existing Investors
Overview And Basis Of Presentation [Line Items]
Cash proceeds received	$ 300