Stockholders' Equity - (Details) - At-the-Market Sales Agreement - USD ($) $ in Millions	1 Months Ended	6 Months Ended
Aug. 31, 2019	Jun. 30, 2020
Common stock reserved
Maximum amount of shares for offering	$ 25.0
Maximum commission percentage	3.00%
Number of shares sold		468,427
Shares available for future issuance		$ 17.7
Sale of common stock
Proceeds from stock offering, net of offering costs		$ 2.1

The aggregate amount of common stock available for future sale under the agreement.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

The maximum amount for aggregate offering and sale of common stock under the agreement.

+ References

No definition available.

+ Details

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- Definition

Represents the commission paid calculated as a maximum percentage of gross proceeds of any sales made pursuant to the Sales Agreement.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	mram_SaleOfStockAbstract
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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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- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

+ Details

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

- Definition

Number of new stock issued during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Period Type:	duration

- Details

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