Intangible Assets - Components of Intangible Assets (Details) - USD ($) $ in Thousands  | 
Jun. 30, 2018  | 
Mar. 31, 2018  | 
|---|---|---|
| Finite Lived Intangible Assets [Line Items] | ||
| Cost | $ 5,826 | $ 5,826 | 
| Accumulated Amortization | (4,930) | (4,595) | 
| Net | 896 | 1,231 | 
| Software | ||
| Finite Lived Intangible Assets [Line Items] | ||
| Cost | 5,826 | 5,826 | 
| Accumulated Amortization | (4,930) | (4,595) | 
| Net | $ 896 | $ 1,231 | 
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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition 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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- Definition Amount before accumulated amortization of intangible assets, excluding goodwill. No definition available. 
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- Definition Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Details 
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