Investment in Aizu Fujitsu Semiconductor Wafer Solution Limited ("AFSW") - Income statement information (Details) - Aizu Fajitsu Semiconductor Wafer Solution Limited - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Mar. 31, 2021
Summary of Variable Interest Entities [Roll Forward]
Beginning balance	$ (1,866)	$ (1,546)	$ (1,546)
Investment	3,765	$ 5,800	6,768
Loss	(3,294)		(6,885)
Gain	1,455		0
Effect of exchange rate change	1		(203)
Ending balance	$ 61		$ (1,866)

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Summary of Variable Interest Entities

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- Definition

Variable Interest Entity, Measure Of Activity, Operating Gain

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Variable Interest Entity, Measure Of Activity, Operating Loss

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Portion of equity (net assets) in a variable interest entity (VIE) not attributable, directly or indirectly, to the parent entity. That is, this is the portion of equity in a VIE that is attributable to the noncontrolling interest (previously referred to as minority interest).

+ References

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The amount of financial or other support the reporting entity has provided (explicitly or implicitly) to the Variable Interest Entity (VIE) that it was not previously contractually required to provide or that the reporting entity intends to provide, including, for example, situations in which the reporting entity assisted the VIE in obtaining another type of support.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123419778&loc=SL6759159-111685

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