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COLLABORATION AGREEMENT (Details)	Sep. 28, 2018	Dec. 15, 2014 USD ($) item	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Collaborative Arrangements [Line Items]
Accrued collaboration charges			$ 1,560,000	$ 1,702,000
Janssen Biotech | Collaboration Agreement
Collaborative Arrangements [Line Items]
Upfront payment received		$ 35,000,000
Number of agreed upon studies | item		2
Percentage of costs to be paid by Geron		50.00%
Percentage of costs to be paid by Janssen		50.00%
Accrued collaboration charges			$ 1,560,000
Transition period	12 months
Maximum period to supply imetelstat during transition period	24 months
Janssen Biotech | Collaborative Arrangement IP Exclusively Licensed
Collaborative Arrangements [Line Items]
Percentage of costs to be paid by Geron		50.00%
Percentage of costs to be paid by Janssen		50.00%

X

- Definition

Carrying value as of the balance sheet date of obligations incurred and payable to collaboration partner for which invoices have not yet been received under the respective collaboration agreement (due within one year or within the normal operating cycle if longer).

+ References

No definition available.

+ Details

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X

- Definition

Represents the percentage of costs that Janssen must pay during certain phases of the agreement.

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No definition available.

+ Details

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- Definition

Represents the percentage of costs that Geron must pay during certain phases of the agreement.

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- Definition

Collaborative arrangement drug supply procurement during transition period maximum.

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- Definition

Represents the number of agreed upon studies.

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No definition available.

+ Details

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- Definition

Collaborative arrangement transition period.

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- Definition

Collaborative arrangements.

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No definition available.

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- Definition

Upfront payment received from Janssen upon effectiveness of Collaboration Agreement.

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- Details

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- Details

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