Represents the term of the agreement.

No definition available.

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- Definition

The amount of expense incurred related to a collaborative agreement.

+ References

No definition available.

+ Details

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- Definition

The amount of the total obligation of an expense related to the collaborative agreement.

+ References

No definition available.

+ Details

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

Compensation expense related to vesting of common stock.

+ References

No definition available.

+ Details

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

- Definition

Represents the period during which the related party possess the exclusive right to manufacture the Company's discrete and embedded ST-MRAM devices developed pursuant to the agreement, after the completion of the relevant statement of work under which the device was developed.

+ References

No definition available.

+ Details

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- Definition

Represents the period during which the related party possess the exclusive right to manufacture the Company's discrete and embedded ST-MRAM devices developed pursuant to the agreement, after the qualification of the MRAM device for a particular technology node.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

The period of time the unvested common shares are subject to repurchase by the Company if the JDA is terminated for any reason, at a price that is the lower of the original price paid by GF or the fair value of the Company?s common stock as of the date of repurchase.

+ References

No definition available.

+ Details

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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

The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

+ References

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Balance Type:	debit
Period Type:	duration

- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	na
Period Type:	duration

- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

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

- Definition

Number of new stock issued during the period.

+ References

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-SubTopic 10
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Significant Agreements (Details) - USD ($) $ / shares in Units, $ in Thousands				1 Months Ended	3 Months Ended
	Aug. 21, 2016	Oct. 21, 2014	Oct. 17, 2014	Sep. 30, 2018	Mar. 31, 2019	Mar. 31, 2018
Joint development agreement
Research and development expense					$ 3,998	$ 6,480
Non-cash compensation expense (income)						$ 237
Common Stock
Joint development agreement
Number of shares sold						3,772,447
Joint Development Agreement [Member] \| Global Foundries, Inc. [Member]
Joint development agreement
Agreement Term			4 years
Period of possession of exclusive right to manufacture after qualification of device			3 years
Period of possession of exclusive right to manufacture after completion of device development work			4 years
Research and development expense					800	$ 2,100
Period to Repurchase Shares		1 year
Joint Development Agreement [Member] \| Global Foundries, Inc. [Member] \| Common Stock
Joint development agreement
Number of shares sold		461,538
Shares sold, price per share		$ 0.00026
Number of shares of common stock, vested	211,538
Joint Development Agreement [Member] \| Global Foundries, Inc. [Member] \| Series B Redeemable Convertible Preferred Stock [Member]
Joint development agreement
Number of shares sold		192,307
Shares sold, price per share		$ 26.00
Collaborative Agreement \| Silterra
Joint development agreement
Non-recurring engineering cost obligation				$ 1,000
JCA costs					$ 100