Fair value of the forward option net asset (liability).

No definition available.

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- Definition

Represents the maximum percentage of total inventory purchased in previous quarter that can be returned by the distributors.

+ References

No definition available.

+ Details

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- Definition

Represents the maximum expense as a percentage of net sales, charged against earnings during the period pertaining to standard and extended warranties on the entity's goods and services granted to customers.

+ References

No definition available.

+ Details

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Represents the period of warranty that the entity's goods and services meet certain specifications. The entity provides these warranties to its customers.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
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-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Definition

Amount of the cumulative effect on retained earnings net of related income tax effect.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22663-107794

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

+ Details

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- Definition

Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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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.

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- References

No definition available.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19279-110258

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- Definition

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14172-108612

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- Definition

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

+ References

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- Definition

Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

+ References

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- References

No definition available.

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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
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-Paragraph 2
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-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6676-107765

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Period Type:	instant

- Definition

Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

+ References

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Period Type:	instant

- Definition

Amount of valuation reserve for inventory.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.BB)
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-Topic 235
-SubTopic 10
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-Paragraph 4
-Subparagraph (SX 210.12-09)
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-SubTopic 10
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=68049868&loc=d3e3927-108312

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- Definition

Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

+ References

+ Details

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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- Definition

Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

The cash inflow associated with the amount received from holders exercising their stock warrants.

+ References

No definition available.

+ Details

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Period Type:	duration

- References

No definition available.

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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Period Type:	instant

- References

No definition available.

+ Details

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Basis of Financial Statement Presentation (Details) - USD ($)			3 Months Ended		6 Months Ended
	Sep. 11, 2017	Apr. 01, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Mar. 31, 2017
Fair Value Assumptions and Methodology for Assets and Liabilities [Abstract]
Money markets			$ 36,726,000		$ 36,726,000		$ 2,055,000
Total debt			(331,787,000)		(331,787,000)		(388,211,000)
NEC TOKIN option, net			0		0		$ (9,900,000)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Change in value of NEC TOKIN option			$ 0	$ 1,600,000	$ 0	$ (10,400,000)
Warrant
Number of shares subject to a warrant held by K Equity, LLC			8,416,814		8,416,814		8,416,815
Share Price			$ 21.57		$ 21.57
Proceeds from Warrant Exercises	$ 8,800,000				$ 8,838,000	$ 0
Class of Warrant or Right, Exercise Price of Warrants or Rights			$ 1.05		$ 1.05
Inventory, Gross [Abstract]
Raw materials and supplies			$ 87,040,000		$ 87,040,000		$ 65,750,000
Work in process			63,194,000		63,194,000		47,408,000
Finished goods			66,987,000		66,987,000		50,738,000
Inventory, gross			217,221,000		217,221,000		163,896,000
Inventory reserves			(17,002,000)		(17,002,000)		(15,941,000)
Inventories, net			$ 200,219,000		$ 200,219,000		147,955,000
Revenue Recognition
Maximum Percentage of Purchased Inventory that Can be Returned by Distributor					6.00%
Period of product warranty					1 year
Warranty costs as a percentage of net sales, maximum			1.00%	1.00%	1.00%	1.00%
Recurring
Fair Value Assumptions and Methodology for Assets and Liabilities [Abstract]
Total debt, fair value			$ (347,263,000)		$ (347,263,000)		(385,251,000)
NEC TOKIN option, net, fair value			0		0		(9,900,000)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Beginning balance		$ (9,900,000)			(9,900,000)
Change in value of NEC TOKIN option					9,900,000
Ending balance			0		0
Recurring \| Money Market Funds [Member]
Fair Value Assumptions and Methodology for Assets and Liabilities [Abstract]
Money markets, fair value			36,726,000		36,726,000		2,055,000
Recurring \| Level 1
Fair Value Assumptions and Methodology for Assets and Liabilities [Abstract]
Total debt, fair value			(341,539,000)		(341,539,000)		(353,000,000)
Recurring \| Level 1 \| Money Market Funds [Member]
Fair Value Assumptions and Methodology for Assets and Liabilities [Abstract]
Money markets, fair value			36,726,000		36,726,000		2,055,000
Recurring \| Level 2
Fair Value Assumptions and Methodology for Assets and Liabilities [Abstract]
Total debt, fair value			(5,724,000)		(5,724,000)		(32,251,000)
Recurring \| Level 2 \| Money Market Funds [Member]
Fair Value Assumptions and Methodology for Assets and Liabilities [Abstract]
Money markets, fair value			0		0		0
Recurring \| Level 3
Fair Value Assumptions and Methodology for Assets and Liabilities [Abstract]
Total debt, fair value			0		0		0
NEC TOKIN option, net, fair value			0		0		(9,900,000)
Recurring \| Level 3 \| Money Market Funds [Member]
Fair Value Assumptions and Methodology for Assets and Liabilities [Abstract]
Money markets, fair value			$ 0		$ 0		$ 0
ASU No. 2016-16
Fair Value Measurement
Cumulative Effect on Retained Earnings, Net of Tax		$ 203,000