Summary of Significant Accounting Policies - Prop Plant and Equip (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Mar. 31, 2016
Property and equipment
Equipment	$ 33,300	$ 35,581
Less: accumulated depreciation and amortization	(19,251)	(18,577)
Property and equipment, net	14,049	17,004
Land and land improvements
Property and equipment
Equipment	425	421
Buildings and building improvements
Property and equipment
Equipment	9,245	11,849
Furniture, fixtures and office equipment
Property and equipment
Equipment	6,997	7,233
Leasehold improvements
Property and equipment
Equipment	162	148
Equipment leased to customers
Property and equipment
Equipment	4,997	4,997
Plant equipment
Property and equipment
Equipment	11,322	10,805
Construction in progress
Property and equipment
Equipment	$ 152	$ 128

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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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://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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+ References

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(13))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Subparagraph (SX 210.5-02(14))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Name Accounting Standards Codification
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