Property, Plant and Equipment - Additional Information (Detail) $ in Millions |
1 Months Ended | 12 Months Ended | |
|---|---|---|---|
|
Feb. 28, 2017
License
|
Dec. 31, 2017
USD ($)
|
Dec. 31, 2016
USD ($)
|
|
| Property, Plant and Equipment [Line Items] | |||
| Depreciation and depletion | $ | $ 0.5 | $ 0.1 | |
| United Kingdom | |||
| Property, Plant and Equipment [Line Items] | |||
| Number of non-operating interest in licenses | License | 2 | ||
| X | ||||||||||
- Definition Depreciation and Depletion No definition available.
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| X | ||||||||||
- Definition Number of non-operating interest in licenses held by entity. No definition available.
|
| X | ||||||||||
- 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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| X | ||||||||||
- Details
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