Related Party Transactions (Details)	3 Months Ended
Mar. 31, 2017 USD ($) ft² $ / shares	Dec. 31, 2016 USD ($)
Related Party Transaction [Line Items]
Carrying value of convertible notes	$ 1,077,000	$ 1,032,000
Rent per month	$ 5,050
Area of office space (in square feet) \| ft²	900
Cell Cure Neurosciences, Ltd. [Member]
Related Party Transaction [Line Items]
Carrying value of convertible notes	$ 2,147,000	1,865,000
Amount of convertible note	2,700,000	2,544,000
Unamortized debt discount	553,000	$ 679,000
Cell Cure Neurosciences, Ltd. [Member] \| Convertible Notes Payable [Member]
Related Party Transaction [Line Items]
Amount of convertible note	$ 614,000
Stated interest rate	3.00%
Conversion price (in dollars per share) \| $ / shares	$ 20.00
Accrued interest is payable period	3 years
Cell Cure Neurosciences, Ltd. [Member] \| Convertible Notes Payable [Member] \| Maximum [Member]
Related Party Transaction [Line Items]
Estimated fair market value (in dollars per share) \| $ / shares	$ 40.00
Intrinsic value (in dollars per share) \| $ / shares	$ 20.00
Effective annual interest rate	23.00%
Cell Cure Neurosciences, Ltd. [Member] \| Convertible Notes Payable [Member] \| Minimum [Member]
Related Party Transaction [Line Items]
Estimated fair market value (in dollars per share) \| $ / shares	$ 28.00
Intrinsic value (in dollars per share) \| $ / shares	$ 8.00
Effective annual interest rate	11.00%
OncoCyte [Member]
Related Party Transaction [Line Items]
Markup rate on allocated costs	5.00%
Interest rate charged on unpaid and overdue invoices	15.00%
Receivables from related party	$ 2,600,000
OncoCyte [Member] \| Maximum [Member]
Related Party Transaction [Line Items]
Term of payment	30 days
Ascendance Biotechnology, Inc [Member]
Related Party Transaction [Line Items]
Receivables from related party	$ 200,000
Asterias Biotherapeutics [Member]
Related Party Transaction [Line Items]
Proceeds from related party	$ 300,000

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Area of land held.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Cash payments to lessor's for use of assets under operating leases.

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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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