Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands  | 
12 Months Ended | |
|---|---|---|
Mar. 31, 2018  | 
Mar. 31, 2017  | 
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| Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] | ||
| Reserve for uncertain income taxes, beginning of period | $ 533 | $ 661 | 
| Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions | (533) | (176) | 
| Interest and penalties on prior reserves | 0 | 48 | 
| Reserve for uncertain income taxes, end of period | $ 0 | $ 533 | 
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- Definition Unrecognized Tax Benefits, Interest and Penalties From Prior Period No definition available. 
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available. 
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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