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Compensation expense related to vesting of common stock.

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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.

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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Cash payments to lessor's for use of assets under operating leases.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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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.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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

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Per share or per unit amount of equity securities issued.

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Number of new stock issued during the period.

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Related Party Transactions (Details)				1 Months Ended	3 Months Ended		12 Months Ended	19 Months Ended
Related Party Transactions (Details)	Aug. 21, 2016 shares	Oct. 21, 2014 $ / shares shares	Oct. 17, 2014	Feb. 28, 2018 shares	Mar. 31, 2018 USD ($) $ / shares shares	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($) $ / shares	Mar. 31, 2018 USD ($) $ / shares shares	Aug. 31, 2016 USD ($) item
Related Party Transactions
Due from related party					$ 382,000		$ 612,000	$ 382,000
Amounts due to related parties					3,734,000		1,694,000	3,734,000
Research and development expense					6,480,000	$ 6,389,000
Number of shares sold \| shares				3,772,447
Non-cash compensation expense (income)					237,000	255,000
Inventory, Net					8,903,000		9,837,000	8,903,000
NXP
Related Party Transactions
Due from related party					382,000		587,000	382,000
Amounts due to related parties					821,000		945,000	821,000
Rent paid					327,000	289,000
Processing costs capitalized in inventory					864,000	427,000
Related party sales					482,000	572,000
NXP \| Wafers
Related Party Transactions
Purchases					157,000	168,000
Product purchased which is included in inventory					652,000		638,000
Joint Development Agreement \| Global Foundries
Related Party Transactions
Agreement Term			4 years
Period to Repurchase Shares		1 year
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
Due from related party					0		25,000,000	0
Amounts due to related parties					2,900,000		$ 749,000	$ 2,900,000
Research and development expense					2,100,000	1,900,000
Number of milestones \| item									3
First milestone payment due per the agreement									$ 569,000
Second milestone payment due per the agreement									650,000
Third milestone payment due per the agreement									$ 406,000
Milestone revenue					$ 0	569,000
Joint Development Agreement \| Global Foundries \| Common Stock
Related Party Transactions
Number of shares sold \| shares		461,538
Shares sold, price per share \| $ / shares		$ 0.00026
Number of shares of common stock, vested \| shares	211,538							182,692
Number of shares of common stock, unvested \| shares					67,307			67,307
Estimated fair value of common stock per share \| $ / shares					$ 7.55		$ 7.50	$ 7.55
Joint Development Agreement \| Global Foundries \| Research and Development
Related Party Transactions
Non-cash compensation expense (income)					$ 237,000	$ 255,000
Joint Development Agreement \| Global Foundries \| Series B Redeemable Convertible Preferred Stock
Related Party Transactions
Number of shares sold \| shares		192,307
Shares sold, price per share \| $ / shares		$ 26.00