Approval of fund to Collaborators

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- Definition

Carrying Value Of Purchased Loans

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- Definition

Class Of Warrant Or Right Exercise Period Of Warrants Or Rights

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- Definition

Debt Instrument Amortized Discount Percentage

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- Definition

Debt Instrument Period During Which Loan Is Subject To Interest Only Payments

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- Definition

Debt Instrument Period During Which Loan Is Subject To Principal And Interest Payments

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- Definition

Fair Value Allocated To Warrant

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No definition available.

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- Definition

Loan Fees

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- Definition

Expiration date of warrants

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No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

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

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- Definition

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

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- Definition

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

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- Definition

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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- Definition

The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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- Definition

Amount of debt issuance costs (for example, but not limited to, legal, accounting, broker, and regulatory fees).

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No definition available.

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The net amount paid or received by the reporting entity associated with purchase (sale or collection) of loans receivable arising from the financing of goods and services.

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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.

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- Definition

Cash received from principal payments made on loans related to operating activities.

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

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Loan Payable - Additional Information (Detail) (USD $)	12 Months Ended	1 Months Ended	14 Months Ended	1 Months Ended
Loan Payable - Additional Information (Detail) (USD $)	Dec. 31, 2014	Apr. 30, 2013	Aug. 31, 2014	Feb. 28, 2015	Jul. 31, 2014	Oct. 31, 2013
Debt Instrument [Line Items]
Proceeds from loan	$ 5,775,543us-gaap_ProceedsFromLoans
Loan term	3 years
Annual interest rate on loan	6.00%
Period of loan subject to interest payments only	6 months
Period of loan subject to principal and interest payments	30 months
Final fee payment at the end of loan term	1,000,000stem_LoanFees
Exercise price of warrant					$ 2.17	$ 1.80
Proceeds received under loan agreement	9,900,000
Initial carrying amount assigned to loan, net of discount	9,512,000stem_CarryingValueOfPurchasedLoans
Fair value allocated to warrant	388,000stem_FairValueAllocatedToWarrant
Cash discount	100,000
Note issuance costs	117,000us-gaap_DebtIssuanceCosts
Deferred financing costs, discount and accretion percentage	9.00%
Common Stock [Member]
Debt Instrument [Line Items]
Number of shares of common stock acquired using warrant	1,180,015
CIRM [Member]
Debt Instrument [Line Items]
Proceeds from loan	5,775,543
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]
Debt Instrument [Line Items]
Repayment of aggregate loan proceeds received				679,000
Silicon Valley Bank Loan Agreement Warrant [Member]
Debt Instrument [Line Items]
Term of warrant expiration	10 years
Exercise price of warrant	$ 1.7034
Warrant expiration period	April 2023
Silicon Valley Bank Loan Agreement Warrant [Member] \| Common Stock [Member]
Debt Instrument [Line Items]
Number of shares of common stock acquired using warrant	293,531
Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Proceeds from loan		9,900,000
Cash discount		$ 100,000