Schedule II - Valuation and Qualifying Accounts - Valuation and Qualifying Accounts (Details) - SEC Schedule, 12-09, Allowance, Credit Loss [Member] - USD ($) $ in Thousands	12 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Balance at Beginning of Year	$ 49	$ 136	$ 6
Additions Charged to Costs and Expense			130
Additions Charged to Other Accounts
Deductions	22	87
Balance at End of Year	$ 27	$ 49	$ 136

Amount of valuation and qualifying accounts and reserves.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

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Amount of increase in valuation and qualifying accounts and reserves from charge to accounts other than cost and expense.

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Amount of decrease in valuation and qualifying accounts and reserves.

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