General - Property Plant Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Property and equipment
Gross property and equipment	$ 451,175	$ 449,735
Accumulated depreciation	(242,138)	(235,939)
Net property and equipment	$ 209,037	213,796
Minimum
Property and equipment
Useful life	1 year
Land
Property and equipment
Gross property and equipment	$ 32,864	32,864
Building
Property and equipment
Useful life	39 years 6 months
Gross property and equipment	$ 35,093	35,094
Machinery and equipment
Property and equipment
Gross property and equipment	$ 145,423	150,921
Machinery and equipment \| Minimum
Property and equipment
Useful life	1 year
Machinery and equipment \| Maximum
Property and equipment
Useful life	10 years
Furniture and fixtures
Property and equipment
Gross property and equipment	$ 35,024	37,157
Furniture and fixtures \| Minimum
Property and equipment
Useful life	3 years
Furniture and fixtures \| Maximum
Property and equipment
Useful life	7 years
Computer software
Property and equipment
Gross property and equipment	$ 80,718	76,495
Computer software \| Minimum
Property and equipment
Useful life	3 years
Computer software \| Maximum
Property and equipment
Useful life	10 years
Leasehold improvements
Property and equipment
Gross property and equipment	$ 104,497	108,717
Leasehold improvements \| Minimum
Property and equipment
Useful life	1 year
Leasehold improvements \| Maximum
Property and equipment
Useful life	11 years
Construction in progress
Property and equipment
Gross property and equipment	$ 17,556	$ 8,487

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
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