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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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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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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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The cash outflow associated with the acquisition of a controlling interest in another entity or an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, joint venture or equity method investment).

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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The amount of purchased research and development assets that are acquired in a business combination have no alternative future use and are therefore written off in the period of acquisition.

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No definition available.

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Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

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Galectin Science LLC - Additional Information (Detail) - Galectin Sciences, LLC - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended			24 Months Ended	36 Months Ended
	Jan. 31, 2014	Dec. 31, 2014	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2014	Dec. 31, 2017	Dec. 31, 2017
Investments in and Advances to Affiliates [Line Items]
Equity method investment in Galectin Sciences LLC	$ 400,000
Subsequent capital contribution		$ 73,000	$ 147,000	$ 164,000			$ 1,547,000
Equity Method Investment, Ownership Percentage	50.00%
Loss from equity method investment in Galectin Sciences, LLC					$ 400,000
Non-cash charge for in-process research and development					$ 200,000
SBH Sciences, Inc
Investments in and Advances to Affiliates [Line Items]
Subsequent capital contribution			$ 35,000			$ 123,000
SBH Sciences, Inc \| In Process Research and Development
Investments in and Advances to Affiliates [Line Items]
Estimated fair value of the IPR&D Contributed by SBH	$ 400,000
Ownership Percentage			80.80%