General - Property Plant Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Property and equipment
Gross property and equipment	$ 473,115	$ 451,175
Less accumulated depreciation and amortization	(266,905)	(242,138)
Total	$ 206,210	209,037
Minimum
Property and equipment
Useful life (years)	1 year
Land
Property and equipment
Gross property and equipment	$ 32,865	32,864
Building
Property and equipment
Useful life (years)	39 years 6 months
Gross property and equipment	$ 35,094	35,093
Machinery and equipment
Property and equipment
Gross property and equipment	$ 149,494	145,423
Machinery and equipment \| Minimum
Property and equipment
Useful life (years)	2 years
Machinery and equipment \| Maximum
Property and equipment
Useful life (years)	10 years
Furniture and fixtures
Property and equipment
Gross property and equipment	$ 36,497	35,024
Furniture and fixtures \| Minimum
Property and equipment
Useful life (years)	3 years
Furniture and fixtures \| Maximum
Property and equipment
Useful life (years)	7 years
Computer software
Property and equipment
Gross property and equipment	$ 94,365	80,718
Computer software \| Minimum
Property and equipment
Useful life (years)	3 years
Computer software \| Maximum
Property and equipment
Useful life (years)	10 years
Leasehold improvements
Property and equipment
Gross property and equipment	$ 110,538	104,497
Construction in progress
Property and equipment
Gross property and equipment	$ 14,262	$ 17,556

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

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