Percentage points subtracted from the reference rate to compute the variable rate on the debt instrument.

No definition available.

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Namespace Prefix:	mram_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of the amount borrowed that must be paid when the loan is prepaid or repaid.

+ References

No definition available.

+ Details

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Namespace Prefix:	mram_
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Balance Type:	na
Period Type:	instant

- Definition

Number of interest and principal payments.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Represents the reimbursement of principal payments per the amended agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	mram_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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Balance Type:	na
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- Definition

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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 210
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-Paragraph 1
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Balance Type:	credit
Period Type:	duration

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

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Debt and Related Warrants - Credit Facility (Details)			1 Months Ended		12 Months Ended
Debt and Related Warrants - Credit Facility (Details)	Jul. 06, 2018 payment	May 04, 2017 USD ($) payment	May 31, 2017 USD ($)	Apr. 30, 2017 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Jun. 30, 2015 USD ($)
Debt
Gain on extinguishment of debt						$ (246,000)
Revolving Loan [Member]
Debt
Loan agreement amount							$ 4,000,000
Repayment of credit facility				$ 1,100,000
Unamortized Debt Issuance Expense				$ 10,000
Term Loan 2015 Credit Facility
Debt
Loan agreement amount							$ 8,000,000
Repayment of credit facility			$ 6,200,000
Payments of Debt Extinguishment Costs			61,000
Unamortized Debt Issuance Expense			$ 175,000
SVB Credit Facility [Member]
Debt
Loan agreement amount		$ 12,000,000
Interest rate					7.77%
Reimbursement of principal payments					$ 1,000,000
End-of-term fee (as a percent)	7.00%	6.00%
SVB Credit Facility [Member] \| Minimum
Debt
Number of interest and principal payments \| payment	24	24
SVB Credit Facility [Member] \| Maximum
Debt
Number of interest and principal payments \| payment	36	36
SVB Credit Facility [Member] \| Prime Rate [Member]
Debt
Interest rate, negative basis spread percentage	0.75%	0.75%
Interest rate					4.75%