Stockholders' Equity - Grants to Directors (Details) - Director - Common Stock $ in Thousands	12 Months Ended
Mar. 31, 2018 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock issuable to Board of Directors for annual service	$ 125
Board of Directors service award measurement period	10 days

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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