Approval of fund to Collaborators

No definition available.

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- Definition

Debt Instrument Principal And Accrued Interest Forgiven

+ References

No definition available.

+ Details

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- Definition

Decrease for amounts of indebtedness forgiven by the holder of the debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(f))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph f

-Article 4

+ Details

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- Definition

Increase for accrued, but unpaid interest on the debt instrument for the period.

+ References

+ Details

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

+ Details

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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- Details

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Commitments and Contingencies - Future Minimum Payments Under All Leases and Loan Payable (Parenthetical) (Detail) (USD $)	12 Months Ended	1 Months Ended	14 Months Ended	1 Months Ended
	Dec. 31, 2014	Apr. 30, 2013	Aug. 31, 2014	Feb. 28, 2015
Loss Contingencies [Line Items]
Proceeds from principal and accrued interest	$ 9,200,000
CIRM [Member]
Loss Contingencies [Line Items]
Approval of fund by California Institute for Regenerative Medicine (CIRM)		19,300,000
Aggregate proceeds from disbursement of the loan			9,600,000
Forgiveness of loan principal	8,917,000
Accrued interest forgiven	243,000
Subsequent Events [Member] \| CIRM [Member]
Loss Contingencies [Line Items]
Repayment of aggregate loan proceeds received				$ 679,000