| Debt - Long-term Capital Lease Obligations Outstanding (Detail) - USD ($) $ in Thousands | Mar. 31, 2021 | Mar. 31, 2020 | 
|---|---|---|
| Debt Disclosure [Abstract] | ||
| Finance lease obligations (Note 8) | $ 55 | $ 95 | 
| Less: current amounts | 21 | 40 | 
| Total | $ 34 | $ 55 | 
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- References No definition available. 
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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