Commitments and Contingencies - Assets Relating to Finance Leases Included in Equipment (Detail) - USD ($) $ in Thousands  | 
Mar. 31, 2020  | 
Dec. 31, 2019  | 
|---|---|---|
| Commitments And Contingencies [Line Items] | ||
| Finance lease assets, gross | $ 162 | $ 198 | 
| Less: Accumulated depreciation and amortization | (517) | (481) | 
| Finance lease assets, net | 162 | 198 | 
| Furniture and Equipment | ||
| Commitments And Contingencies [Line Items] | ||
| Finance lease assets, gross | $ 679 | $ 679 | 
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- Definition Commitments and contingencies. No definition available. 
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- Definition Finance lease right of use asset accumulated depreciation and amortization. No definition available. 
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- Definition Finance lease right of use asset net. No definition available. 
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- Definition Amount of lessee's right to use underlying asset under finance lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Details 
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