Income Taxes - Additional Information (Detail) - USD ($) |
9 Months Ended | |
|---|---|---|
Sep. 30, 2018 |
Sep. 30, 2017 |
|
| Income Tax Disclosure [Abstract] | ||
| Current income tax expense or benefit | $ 0 | $ 0 |
| Deferred income tax expense or benefit | 0 | $ 0 |
| Tax Cuts and Jobs Act, Adjustments of provisional income tax expense benefit | $ 0 | |
| X | ||||||||||
- Definition Tax cuts and jobs act of 2017 incomplete accounting adjustments of provisional income tax expense benefit. No definition available.
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| X | ||||||||||
- Definition Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- References No definition available.
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