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

No definition available.

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- 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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Period Type:	instant

- Definition

Represents the fair value of warrants.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Represents the number of months that interest only payments are made per the agreement.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Represents the number of months of equal principal payments plus accrued interest are made per the agreement.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Represents the value if the option to put the common stock warrants to the Company upon expiration or a liquidity event; to be prorated if the Bank exercises a portion of the warrant.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Represents the prepayment fee, as a percentage of the total commitment.

+ References

No definition available.

+ Details

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

- Definition

Represents the early termination fee of a debt instrument as a percentage of the maximum availability under the facility.

+ References

No definition available.

+ Details

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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Face amount or stated value per share of common stock.

+ References

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Data Type:	num:perShareItemType
Balance Type:	na
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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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-SubTopic 20
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	credit
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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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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Balance Type:	na
Period Type:	duration

- 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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- 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

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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

- Definition

Amount of income (expense) related to nonoperating activities, classified as other.

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Debt - Credit Facility (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended		3 Months Ended
	Aug. 05, 2019	Jul. 31, 2020	Jun. 30, 2020	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Jul. 15, 2020	Jul. 31, 2019
Debt
Common stock, par value				$ 0.0001		$ 0.0001	$ 0.01
Outstanding balance				$ 2,000
Other (expense) income				(15)	$ 48
2017 Credit Facility
Debt
Repayment of credit facility				800
Principal amount								$ 8,000
2019 Credit Facility
Debt
Number of shares the warrant can be converted to	9,375						21,500
Warrant exercise price	$ 8.91
Amount bank could receive if takes the option to put the warrants upon expiration or a liquidity event	$ 50
Fair value of warrants							$ 152
Principal amount				7,820		$ 8,420
Outstanding balance				5,400
Other (expense) income				$ (4)	$ 5
2019 Credit Facility \| Prime Rate
Debt
Effective interest rate				3.75%
2019 Credit Facility - Revolving Line Of Credit
Debt
Loan agreement amount				$ 5,000
Agreement term				2 years
Interest rate, basis spread percentage				1.50%
Effective interest rate		4.75%	6.75%	10.18%
Commitment fee (as a percentage)				1.60%
Termination fee (as a percentage)				1.00%
Unused facility fee (as a percentage)				0.125%
Debt amount				$ 2,000
Remaining availability				$ 3,000
2019 Credit Facility - Revolving Line Of Credit \| Prime Rate \| Minimum
Debt
Interest rate, basis spread percentage				4.75%
Effective interest rate				4.75%
2019 Credit Facility - Term Loan
Debt
End-of-term fee (as a percent)				7.00%
Agreement term				46 months
Effective interest rate		3.75%	4.75%	7.85%
Prepayment fee (as a percentage)				2.00%
Debt amount				$ 6,000
Number of months of interest only payment		16 months	12 months	16 months
Number of months of equal principal payments plus accrued interest				30 months
2019 Credit Facility - Term Loan \| Prime Rate
Debt
Interest rate, negative basis spread percentage				0.75%
Effective interest rate				3.75%