Debt - 2017 Facility - Additional Information (Details)		1 Months Ended
May 04, 2017 USD ($) payment	Apr. 30, 2017 USD ($)
Term Loan 2015 Credit Facility
Debt
Repayment of credit facility		$ 6,200,000
Unamortized debt discount		175,000
Prepayment penalty		61,000
Revolving loan 2015 Credit Facility
Debt
Repayment of credit facility		1,100,000
Unamortized debt discount		$ 10,000
2017 Credit Facility
Debt
Loan agreement amount	$ 12,000,000
End-of-term fee (as a percent)	6.00%
2017 Credit Facility \| Prime Rate
Debt
Interest rate	3.50%
Interest rate, negative basis spread percentage	0.75%
2017 Credit Facility \| Minimum
Debt
Number of interest and principal payments \| payment	24
2017 Credit Facility \| Maximum
Debt
Number of interest and principal payments \| payment	36

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

No definition available.

Name:	mram_DebtInstrumentNegativeBasisSpreadOnVariableRate
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

Name:	mram_EndOfTermFeePercentage
Namespace Prefix:	mram_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of interest and principal payments.

+ References

No definition available.

+ Details

Name:	mram_NumberOfInterestAndPrincipalPayments
Namespace Prefix:	mram_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- 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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

Name:	us-gaap_ExtinguishmentOfDebtAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow for incremental, external costs directly pertaining to an early extinguishment of debt, including legal costs and prepayment penalties, and excluding interest and repayment of debt principal.

+ References

No definition available.

+ Details

Name:	us-gaap_PaymentsOfDebtExtinguishmentCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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

+ Details

Name:	us-gaap_UnamortizedDebtIssuanceExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_CreditFacilityAxis=mram_TermLoan2015CreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=mram_SiliconValleyBankCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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- Details

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