Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Amortizing Intangibles:
Finite-Lived Trademarks, Gross	$ 15,474	$ 7,207
Goodwill	40,294	40,294
Trademarks	15,474	7,207
Carrying Amount	67,031	39,527
Accumulated Amortization	22,598	(16,953)
Total amortization	44,433	56,480
Intangible Assets, Net (Including Goodwill)	59,907	63,687
Intangible assets	82,505	46,734
Patents [Member]
Amortizing Intangibles:
Finite-Lived Patents, Gross	26,662	26,660
Accumulated Amortization	(10,625)	(9,204)
Total amortization	$ 16,037	$ 17,456
Customer Relationships
Amortizing Intangibles:
Useful life	12 years 3 months 12 days	15 years 8 months 6 days
Accumulated Amortization	$ (11,735)	$ (7,535)
Total amortization	28,396	5,118
Finite-Lived Customer Relationships, Gross	40,131	12,653
Other Intangible Assets [Member]
Amortizing Intangibles:
Accumulated Amortization	(238)	(214)
Total amortization	0	0
Other Finite-Lived Intangible Assets, Gross	$ 238	$ 214
Purchased technology, customer relationships and patents \| Weighted-average
Amortizing Intangibles:
Useful life	15 years 9 months 12 days
Purchased technology, customer relationships and patents \| Minimum
Amortizing Intangibles:
Useful life	3 years	3 years
Purchased technology, customer relationships and patents \| Maximum
Amortizing Intangibles:
Useful life	18 years	18 years

Gross carrying amount before accumulated amortization as of the balance sheet date to an asset acquired in a business combination representing a favorable existing relationship with customers having a finite beneficial life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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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.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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- Definition

Gross carrying amount before accumulated amortization as of the balance sheet date of the costs pertaining to the exclusive legal rights granted to the owner of the patent to exploit an invention or a process for a period of time specified by law. Such costs may have been expended to directly apply and receive patent rights, or to acquire such rights.

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Gross carrying amount before accumulated amortization as of the balance sheet date for the rights acquired through registration of a trademark to gain or protect exclusive use of a business name, symbol or other device or style for a specified period of time.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Carrying amount (original costs adjusted for previously recognized amortization and impairment) as of the balance sheet date for the rights acquired through registration of a trademark to gain or protect exclusive use of a business name, symbol or other device or style for a projected indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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Carrying amount of finite-lived intangible assets, indefinite-lived intangible assets and goodwill. Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Intangible assets are assets, not including financial assets, lacking physical substance.

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Amount before accumulated amortization of finite-lived intangible assets classified as other.

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