Derivative Instruments and Hedging Activities (Effect on Consolidated Statements of Operations) (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Derivatives designated as hedging instruments \| Foreign currency contracts \| Other comprehensive income
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in other comprehensive income (effective portion), net of taxes	$ (1,404)	$ (892)	$ (580)
Derivatives designated as hedging instruments \| Foreign currency contracts \| Selling, general & administrative expenses
Derivative Instruments, Gain (Loss) [Line Items]
Amounts reclassified from AOCI into results of operations (effective portion), net of taxes	1,804	799	528
Derivatives not designated as hedging instruments \| Interest-rate swaps \| Interest expense (income), net
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) recognized in results of operations	$ 0	$ 0	$ 399

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a),(c),(d),(e)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959

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- Definition

The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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