Equipment (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2014
Equipment, furniture and fixtures [Abstract]
Equipment, furniture and fixtures	$ 4,870,516us-gaap_PropertyPlantAndEquipmentGross	$ 4,431,586us-gaap_PropertyPlantAndEquipmentGross
Construction in progress	405,730us-gaap_ConstructionInProgressGross	0us-gaap_ConstructionInProgressGross
Accumulated depreciation	(2,418,400)	(1,433,853)
Equipment net of accumulated depreciation	2,857,846us-gaap_PropertyPlantAndEquipmentNet	2,997,733us-gaap_PropertyPlantAndEquipmentNet
Equipment, furniture, and fixtures included in capital lease borrowings				115,000us-gaap_CapitalLeaseObligations
Leasehold improvements for Asterias' facility	405,730us-gaap_LeaseholdImprovementsGross
Depreciation expense	1,050,651us-gaap_Depreciation	656,759us-gaap_Depreciation	386,457us-gaap_Depreciation
Increase in accumulated depreciation	984,547
Tenant Improvement Allowance Under Lease Agreement	$ 4,400,000

Amount of allowance for tenant related to lease agreement which use to construct a laboratory and production facility.

No definition available.

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Name Regulation S-X (SX)

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The change during the period, from the beginning balance of accumulated depreciation, depletion and amortization (relating to property, plant and equipment) to the ending balance.

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- Definition

Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

+ References

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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